Vehicle troubleshooting

The description of diagnostics of electronic control systems and codes of malfunctions are given in the Chapter Engine Electrical Systems.

This section proposes the simplest scheme for finding out the causes of malfunctions and failures occurring in vehicle components and systems. Failures and their possible causes are grouped according to their relation to certain components or systems of the vehicle, such as engine, cooling system, etc., in addition, the text provides links to chapters and sections related to these problems.

Remember that the successful completion of troubleshooting is determined by the integrity of a combination of good knowledge and a patient, systematic approach to investigating the problem. You should always move from simple to complex, bring each check to its logical conclusion and try not to miss obvious facts - anyone can forget to fill the fuel tank or leave lights on at night.

And finally, you should always try to get a clear picture of the development of the malfunction and take appropriate steps to prevent recurrence. If the failure of the electrical equipment occurred due to a violation of the quality of the contact, check at the same time the condition of all other contacts and electrical connectors of the system. If the same fuse has blown several times in a row, there is no point in replacing it further - try to find out the cause of the failure. Remember that the failure of a minor component may be a sign of a malfunction of a more important node or the entire system.

Engine

Mandatory conditions for starting any gasoline engine are the correct supply of the air-fuel mixture to the cylinders and the adequacy of sparking on the spark plugs.

First of all, you should make sure that the fuel supply is working properly.

To determine if a spark is formed, unscrew the spark plugs, insert them into the tips and attach them individually to the ground. In this case, do not hold the wire or tip with your hands - use insulated pliers. Have an assistant start the engine. If there is no spark, try to determine the cause of the failure.

Engine won't crank when trying to start it

• The battery terminals are oxidized or the wire lugs are loose on them.
• The battery is discharged or defective. If the wire lugs are not oxidized and are securely attached to the battery terminals, turn the ignition key to the «ON», then turn on the headlights and/or windshield wipers - if they do not work, the battery is low.
• Transmission incorrectly set to position «P» (AT) or into neutral (RKPP), or the clutch is not fully depressed.
• An open in the starting system circuit.
• Starter gear is stuck in drive disc/flywheel ring gear.
• Faulty starter relay.
• Starter defective.
• Faulty ignition switch.

Engine cranks but won't start

• Wrong start up (see Section Starting and shutting down the engine, starting to move).
• Faulty or disabled engine immobilizer.
• Faulty fuel pump safety switch.
• The fuel tank is empty, or low-quality fuel is filled.
• The air filter is heavily soiled. There are vacuum leaks in the air supply elements, malfunctions in the fuel injection and ignition control system.
• Low battery (engine cranks too slowly).
• The battery terminals are oxidized or the wire lugs are loose on them.
• The fuel pump is faulty, or its relay is damaged - check by ear that the pump is turned on when the ignition is turned on.
• Damaged or excessively wet components of the ignition system.
• Worn or defective spark plugs, or incorrectly set spark plug gap.
• An open in the starting system circuit.
• The wiring to the ignition coil is broken or disconnected, or the wires are loose at the coil terminals.
• The fuse of the engine control unit is damaged, any of the sensors of the engine management system is faulty.
• Low compression pressure.

The starter operates without cranking the engine

• Stuck starter gear.
• Worn or damaged starter gear teeth or flywheel ring/drive plate.

Difficulty starting a cold engine

See also Section Cold engine starts badly, works unstably.

• Low battery.
• The serviceability of the functioning of the components of the power system or electrical equipment is broken.

Difficulty starting a hot engine

See also Section A warm engine does not start well, runs erratically.

• Air filter blocked.
• The serviceability of the functioning of the components of the power system or electrical equipment is broken.
• Fuel is not being delivered to the fuel injectors.
• Insufficient compression in the cylinders.

Starter engagement is too noisy or difficult

• Worn or damaged starter gear teeth or flywheel ring/drive plate.
• Lost or insufficiently tightened starter mounting bolts.

Engine starts but immediately stalls

• Faulty engine immobilizer.
• The wiring is faulty, or the wires are loose at the terminals of the ignition coil or generator.
• The functioning of the components of the power system or electrical equipment is broken.
• The basic settings of the engine control unit are violated (ECM).
• There is damage in the exhaust system and reduce the toxicity of exhaust gases (OG).
• There is vacuum loss at the throttle body, intake manifold, or through the vacuum hoses.

The stability of the engine at idle is broken

• There are vacuum losses. Make sure that the fasteners are securely tightened, check the fact and quality of fastening on your fittings on the inlet pipeline of all vacuum hoses. Listen to the running engine with a stethoscope or a piece of fuel hose - a hissing sound indicates a leak. Equally effective is the use of a soapy solution for testing.
• The functioning of the components of the power system or electrical equipment is broken.
• Violated patency of the valve of the controlled crankcase ventilation system (PCV).
• Air filter blocked.
• The fuel pump is not supplying enough fuel to the injectors.
• There are leaks through the cylinder head gasket - measure the compression in the engine cylinders (see chapter Engine).
• Camshaft lobes worn out.

Cylinder misfiring at idle

• Worn or dirty spark plugs or incorrect spark plug gap.
• There is a malfunction of the components of the power system or electrical equipment.
• Faulty I/O wiring.
• Low-quality fuel is filled, or the fuel filter is blocked.
• There is a loss of vacuum in the intake manifold or through the hose connections.
• Low or unevenly distributed compression in the cylinders.
• The operation of the engine control system is disrupted.

There are gaps in the operation of the engine cylinders when the vehicle is moving in gear

• The fuel filter is blocked or the fuel system is contaminated.
• Faulty or dirty spark plugs or incorrect spark plug gap.
• There is a malfunction of the components of the power system or electrical equipment.
• Faulty I/O wiring.
• Components of system of decrease in toxicity of the fulfilled gases are faulty.
• Low or unevenly distributed compression in the cylinders.
• Faulty ignition system.
• There is vacuum loss at the throttle body, intake manifold, or through the vacuum hoses.

The engine spontaneously stalls

• Idle speed control broken.
• The patency of the fuel filter is broken, or moisture or dirt has got into the power system.
• There is a failure of the components / information sensors of the power system.
• Components of systems of decrease in toxicity of the fulfilled gases are faulty.
• Faulty or dirty spark plugs or incorrect spark plug gap.
• There is vacuum loss at the throttle body or through the vacuum hoses.

The engine does not develop full power

• There is a malfunction of the components of the power system or electrical equipment.
• Air cleaner clogged.
• Faulty spark plugs or incorrect spark plug gap.
• Faulty ignition coil.
• ATF level dropped (see chapter Vehicle settings and routine maintenance).
• Clutch slips / AT.
• Blocked fuel filter and/or dirt/moisture in the fuel system.
• Filled with poor quality fuel.
• Low or unevenly distributed compression in the cylinders.

There are pops in the intake system or shots in the exhaust system

• The functioning of the components of the power system or electrical equipment is broken.
• There is a defect in the secondary circuit of the ignition system (destruction of spark plug insulators or damage to I/O wires).
• The fuel injection system needs to be adjusted, or its components are excessively worn.
• There is vacuum loss at the throttle body, intake manifold, or through the vacuum hoses.
• Seizes valves.
• I/O wire connection is out of order.

Detonation sounds occur when accelerating or going uphill

• Filled with poor quality fuel.
• The functioning of the components of the power system or electrical equipment is broken.
• Wrong type spark plugs installed.
• The basic settings of the ECM have been violated.
• Faulty knock sensor.
• There are vacuum losses.

The engine continues to run after the key is turned to «OFF»

• Excessively high idle speed.
• There is a malfunction of the electrical equipment or components of the engine management system.
• Faulty canister purge valve of the evaporative emission system (EVAP).
• High engine operating temperature (the coolant level has dropped, the thermostat is faulty, the radiator is blocked or the water pump is faulty).
• The tightness of the injectors is broken.

Engine electrical equipment

Decreased capacity or insufficient battery power

• The alternator drive belt is worn or damaged, or its tension adjustment is broken.
• The electrolyte level is insufficient or the battery is badly discharged.
• The battery terminals are oxidized or the wire lugs are loose on them.
• The alternator does not provide the required charging current.
• An open circuit in the wiring of the charging circuit.
• Short circuit on «mass» electrical wiring creates a constant leakage of current generated by the battery.
• There is an internal defect in the battery.

The charging indicator lamp does not go out when the rpm is increased

• Loose drive belt tension.
• Damaged voltage regulator and/or alternator. Disconnect the wire (D+) on the back of the generator and turn on the ignition. Next, check the condition of the generator voltage regulator.
• Worn alternator brushes.
• Damaged wire between generator and voltage regulator.
• Faulty instrument cluster.

The charging indicator lamp does not light up when the key is turned to the «ON»

• The control lamp is out of order.
• Generator defective.
• There is a defect in the printed circuit board, wiring inside the instrument cluster unit or lamp socket.

The charging indicator lamp does not go out when the key is turned to the «OFF»

• Broken diodes.

Starter

Attention! The contact terminals of the electrical wiring must be securely fastened and not oxidized!

• If the starter does not turn, first make sure that there is voltage at terminal No. 50 of the traction relay (minimum 10 V). If negative, check the condition of the starter current circuit wiring.
• To verify that the starter engages properly at full battery voltage, do the following:
• With no gear engaged, turn the key to position «ON»;
• Bridge terminals 30 and 50 of the starter with a wire with a cross section of at least 4 mm².
• If the starter works flawlessly, the cause of the malfunction should be sought in the wires to the starter. If the starter does not work, it should be checked in the removed state.

Starter does not turn when key is turned to «START»

• Low battery.
• Bridge terminals 30 and 50 of the starter: if it rotates, check the wire 50 connected to the ignition switch for an open, also evaluate the condition of the starter switch.
• The ground wire is broken, or the quality of its terminal connection is broken.
• The weakening of the current strength due to a violation of the quality or oxidation of the contact connections.
• There is no voltage at terminal 50 of the traction relay as a result of a broken electrical wiring or damage to the starter switch.

The starter rotates slowly and does not turn the crankshaft

• Low battery.
• Filled with summer oil.
• The passage of current is difficult due to poor-quality contacts.
• The carbon brushes are loose on the commutator, stuck in the guides, worn, broken, oily or dirty.
• Insufficient distance between brushes and commutator.
• Collector in grooves or burnt and oily.
• No voltage at terminal 50 (minimum 8 V).
• Broken bearing.
• Faulty traction relay.

Starter «grasps», but provides cranking the engine only jerkily

• Defective gear drive.
• The gear is dirty.
• Drive disc ring gear damaged.

Starter gear does not disengage from flywheel/drive plate ring gear

• Dirty or damaged gear drive components.
• Faulty traction relay.
• The return spring is weak or broken.

The starter continues to work after the ignition key is released

• The traction relay is jammed - immediately turn off the ignition and replace the traction relay.
• The ignition lock does not turn off - disconnect the battery, replace the lock.

Supply system

Excessive fuel consumption

• Air filter dirty or blocked.
• Insufficient tire inflation pressure or wrong size tires fitted.
• The engine has mechanical damage. Check the compression, if necessary, make the appropriate reconditioning.
• Excessively high idle speed and maximum crankshaft speed.
• There is a malfunction of the components of the power system, electrical equipment or electronic control.
• Leaks in the air intake system.
• There are damages in the exhaust system and reduce the toxicity of the exhaust gas.

There are fuel leaks and/or the smell of gasoline

• There are leaks in the fuel lines or vent lines.
• The fuel tank is full. Refuel only until the gun automatically shuts off.
• There are leaks/evaporation from the lines of power supply systems and reduction of exhaust gas toxicity.

Engine won't start

• When the starter is turned on, the fuel pump does not work (I don't hear the noise of his work). Tap the pump body lightly to loosen the stuck part. Check the voltage supply to the pump (check that the fuse is working and that the contact terminals of the corresponding electrical wiring are securely fastened).
• Faulty fuel pump relay.
• Stuck injector valves. Check injectors, replace if necessary. Check the voltage supply to the injectors.
• No signal from ignition sensor or ECT sensor. Check the condition of its electrical wiring, poll the memory of the OBD II system.
• Fuel lines damaged, clogged or leaking, hoses defective.
• Fuel filter clogged.
• Excess air is sucked into the intake tract as a result of leakage.
• Vacuum pipes are damaged, or there is a violation of the tightness of their fit.
• Damaged fuel pressure regulator - check residual pressure.
• Damaged throttle position sensor (TPS).
• No power to ECM.
• Clogged fuel tank ventilation lines, clogged filter in the tank.
• The moment of the start of fuel supply is knocked down.

Cold engine starts badly, works unstably

• The CO content is out of specification - measure accordingly, check idle speed.
• Faulty ECT sensor.
• The fuel pressure does not match the required value.
• Excess air is sucked into the intake tract as a result of leakage.

A warm engine does not start well, runs erratically

• Leaky air intake system. Check intake system. To do this, leave the engine to idle and moisten the seals and connections on the intake tract with gasoline. If the speed increases for a short time, repair leaks.
• Damaged fuel pump check valve.
• Leaks in the fuel system.
• Increased fuel pressure in the power system.
• Malfunction of the EVAP system.
• Clogged or kinked fuel return line to tank.
• Stuck injector valves. Check injectors, replace if necessary. Check the voltage supply to the injectors.
• No signal from Hall ignition sensor or coolant temperature sensor. Check the condition of the relevant electrical wiring, interrogate the OBD II system.
• Excess air is sucked into the intake tract as a result of leakage.
• Pressure regulator damaged - check residual pressure.
• Damaged TPS sensor.
• No power to ECM.

Engine runs intermittently

• The fuel pump wiring connections are broken from time to time. Check wiring connectors and fuses for fuel pump, MAP sensor, and fuel pump relay.
• Poor fuel quality, vapor lock formation.
• Weak fuel supply.
• Fuel filter clogged.
• Fuel pump defective.
• Faulty injectors.
• The lambda probe is faulty, there are disturbances in the mixture quality control circuit or there is no heating of the lambda probe.
• Faulty TPS.
• Damaged exhaust manifold or exhaust pipe (there are exhaust gas leaks).
• Malfunction of the EVAP system.
• Stuck injector valves. Check injectors, replace if necessary. Check the voltage supply to the injectors.
• No signal from Hall ignition sensor or ECT sensor. Check wiring, poll ECM memory for trouble codes.
• Excess air is sucked into the intake tract as a result of leakage.
• Damaged or leaking vacuum lines
• Pressure regulator damaged - check residual pressure.
• No power to ECM.

The engine runs intermittently during transients and at idle

• Leaky air intake system. Check intake system connections. Start the engine and moisten the connections of the suction tract components with gasoline. If the engine speed briefly increases, eliminate the cause of the leak.
• Incorrect idle adjustment. Check TPS and lambda adjustment.

Hot engine won't start

• Incorrect adjustment of the CO content. Check CO content and idle speed.
• Too high pressure in the fuel system - check the fuel pressure, if necessary, replace the pressure regulator.
• Clogged or bent return line between pressure regulator and fuel tank. Clean or replace piping.
• Faulty engine temperature sensor.
• The tightness of the power supply system is broken.
• The tightness of the intake air duct is broken.

Engine running after shutdown

• Leaky injectors. Check injectors.

Lubrication system

The control lamp does not light up when the key is turned to position «ON»

• Defective oil pressure sensor. Turn on the ignition, disconnect the wire from the sensor and short it to «mass», - if the lamp lights up, replace the sensor.
• The sensor is not energized, the contacts are corroded - check the condition of the relevant wiring.
• The control lamp is faulty.
• Faulty instrument cluster.

The control lamp does not go out after starting the engine

• The oil is overheated. If the control lamp goes out after applying gas, nothing needs to be done.

The control lamp does not go out after applying gas, or lights up while driving

• The oil level has dropped.
• There is a short circuit in the wiring of the oil level sensor.
• Sensor defective.

Too low oil pressure at all speeds

• The oil level has dropped.
• Clogged oil pickup strainer in sump.
• Worn oil pump.
• Damaged crankshaft bearings.

Too low oil pressure at low speeds

• Pressure reducing valve stuck open due to contamination.

Oil pressure too high at engine speeds above 2000 rpm

• Pressure reducing valve does not open due to contamination.

Cooling system

Overheat

• The coolant level has dropped.
• The water pump drive belt is worn or damaged or its tension adjustment is broken.
• The internal channels of the radiator are blocked or dirty (blocked) radiator grille.
• Faulty thermostat.
• Broken or cracked fan blades.
• Faulty sensor-switch (D/V) fan.
• Faulty coolant temperature gauge (coolant).
• Water pump defective.
• The radiator cap does not hold pressure - check the cap under pressure.

Hypothermia

• Faulty thermostat.
• Inaccurate readings of the coolant temperature meter.

External coolant leaks

• The hoses are damaged or destroyed as a result of aging of the material or their fastening on the fittings has loosened.
• The seals of the water pump are damaged, - the coolant oozes through the control hole in the pump housing.
• There are leaks from the internal channels of the radiator or tank.
• There are leaks from the engine drain plug or water gallery squeeze plugs.

Internal coolant leaks

Note. Internal coolant leaks are usually identified by checking the condition of the engine oil. Inspect the feeler blade and inside surfaces of the cover (lids) cylinders for traces of water and oil foaming.

• There are leaks through the cylinder head gasket - check the cooling system with pressure.
• There are cracks in the cylinder walls or in the head casting.

Loss of coolant occurs

• Too much coolant has been added to the system.
• Coolant boils away as a result of engine overheating.
• There are internal or external coolant leaks.
• Radiator cap defective - check the cap with pressure.

Coolant circulation interrupted

• The water pump is not functioning properly. The easiest way to verify the operation of the pump is to pinch the upper radiator hose while the engine is idling. If a push of liquid is felt inside the hose when the hose is released, the pump is functioning properly.
• The patency of the cooling system is broken - flush it and fill it with fresh liquid. If necessary, remove the radiator and backflush it.
• The water pump drive belt is worn or damaged or its tension adjustment is broken.
• Stuck thermostat.

Heater

Heater fan not working

• The fan e/motor fuse is defective.
• Faulty fan switch - check if voltage is applied to the pre-resistors, remove and check the fan switch.
• The e/motor of the fan is faulty. Check if it is receiving voltage with the ignition on and the fan switch closed - if voltage is supplied, replace the motor.

The heater fan does not work on one of the stages

• Faulty preresistor.

The heater is not switched off by the regulator

• Switch defective.
• Control mixing flap cables are damaged or not movable.

Heating power too low

• Insufficient coolant level.
• The heater control handles are hard to move - check the control assembly, if necessary, replace the corresponding drive cable.

Noise in the heater fan area

• Dirt, leaves got in - remove the fan and clean it, clean the air channel.
• The impeller balance is broken, the bearing is damaged.

Clutch

Clutch won't disengage (the manual transmission control lever does not move freely into the reverse gear position and back when the clutch pedal is depressed to the floor)

• Bent or damaged clutch disc (see chapter Drive shafts, steering knuckles and hub assemblies).

Clutch slips (engine speed increases without increasing vehicle speed)

• The clutch disc is oily or its friction linings are worn out. Remove the clutch (see chapter Drive shafts, steering knuckles and hub assemblies) and check the status of its components.
• Clutch disc not worn in properly. It may take 30 to 40 normal starts of the car to finally break in a new disc.
• Worn pressure plate/clutch basket (see chapter Drive shafts, steering knuckles and hub assemblies).

Vibration occurs when clutch is engaged

• Oily clutch disc. Remove the clutch and check the condition of its components. Repair any leaks found.
• Worn disc hub splines (clutch disc). Remove the clutch and check the condition of its components.
• Bent pressure plate/clutch basket or flywheel. Remove the clutch and check the condition of its components and flywheel.

Jerks during clutch operation

• Damage to engine and gearbox mounts. Check, replace if necessary.
• Weakening of the gearbox to the suspension. Tighten the mounting bolts.
• Uneven pressure plate contact. Replace clutch basket.
• The crankshaft is not centered with the gearbox. Check centering.

Squealing or rattling occurs when the clutch is fully engaged (pedal released)

• Clutch release bearing stuck. Remove the clutch and check the condition of the bearing. Remove all burrs and nicks and lubricate the bearing before reinstalling.

Squealing or rattling occurs when the clutch is fully disengaged (pedal depressed)

• Worn or damaged release bearing (see chapter Drive shafts, steering knuckles and hub assemblies).
• Worn or damaged springs (or aperture blades) pressure plate in the clutch basket (see chapter Drive shafts, steering knuckles and hub assemblies).

Clutch pedal remains depressed to the floor after releasing it

• Stuck clutch master or slave cylinder piston. Damage to the clutch hydraulic system or release bearing. Check the condition, if necessary, remove the clutch components.

Manual gearbox (RKPP)

When the manual transmission is set to neutral, extraneous noises occur during engine operation

• Worn input shaft bearing.
• Drive shaft bearing damaged.
• Worn intermediate shaft bearings.
• Worn or damaged washers for adjusting the axial play of the intermediate shaft.

Extraneous noises occur in any position of the manual transmission

• Any of the above reasons and/or:
• Insufficient amount of gear oil is filled in the manual transmission (his level dropped).

Extraneous noise occurs in any particular gear

• Worn, damaged or chipped gear teeth of this gear.
• Worn or damaged synchronizer of this gear.

Going on «jumping off» Manual transmission with top gear

• Dirt has got between the gearbox boat and the engine or the gearbox has shifted in relation to the engine.

Complications occur when shifting gears

• Not fully squeezed out (turned off) clutch.
• Shift rod damaged, loose or out of adjustment. Make a thorough check of the condition of the components, if necessary, replace the defective ones.

Transmission oil leaks

• The manual transmission is filled with an excessive amount of gear oil. Drain excess if necessary.
• The differential seals need to be replaced.

Automatic transmission (AT)

Due to the complexity of the AT design, it is advisable to carry out diagnostics of its malfunctions and repair of components in a car service workshop.

General problems associated with the functioning of the switching mechanism

• Among the failures associated with a violation of the adjustment of the shift rod are the following:
• The engine can be started in transmission positions other than "R" And "N";
• The transmission position indicator reading is different from the actual gear selected;
• The vehicle is moving with the transmission in position "R" or "N";
• Transfers are switched with difficulty or arbitrarily.
• Adjust the shift rod.

Transmission slips, shifts hard, makes strange noises or does not move the car when set to one of the gears

• There are many possible causes of the problems listed in the title, but only one of them falls under the competence of an amateur mechanic - the wrong level of transmission fluid (ATF).
• Before driving the car to a car service workshop, check the ATF level and condition. Correct the ATF level or change it.

Transmission fluid leaks (ATF)

• ATF is dark red in color. Traces of its leaks should not be confused with traces of impellent oil, which can be carried to the transmission crankcase by the oncoming air flow.
• To identify and locate the source of the leak, first remove all traces of dirt and grease from the transmission boat. Use a suitable degreaser and/or steam clean. Then drive the car for a short trip at low speed (so that traces of the leak are not carried away by the oncoming flow far from its source). Stop, jack up the vehicle and locate the source of the leak by visual inspection. Most often these are:
• Transmission oil pan, - tighten the fixing bolts and/or replace the oil pan gasket;
• ATF fill tube, - replace the rubber seal at the point where the tube enters the transmission housing;
• ATF lines, - tighten fittings or replace lines;
• Ventilation tube - Transmission is overfilled and/or water has entered it.

ATF is brown or smells like burning

• Insufficient ATF level.

Kickdown mode does not turn on when fully depressing the pedal (no downshift)

• Dropped ATF level.
• Faulty engine management system.
• Faulty sensor-switch or its wiring.
• Adjustment of a drive cable of the selector is broken.

The engine does not start in any position of the selector or starts in positions other than «R» And «N»

• The adjustment of the sensor-switch of permission to start is violated.
• The correct functioning of the engine management system is broken.
• Selector cable out of adjustment.

Transmission slips, jerks or noises when shifting gears. The car does not move when the modes are turned on «D» or «R»

• Dropped ATF level.
• The sensor or its wiring is faulty.
• The correct functioning of the engine management system is broken.

Bridges

Extraneous noise

• Ordinary road noise - can not be adjusted.
• Tire noise - check the condition of the treads and tire inflation pressure.
• Worn or damaged wheel bearings or loose torque.

Vibrations

• Check the condition of the wheel bearings by alternately jacking up the appropriate corner of the vehicle and rotating the wheel by hand. Listen for sounds coming from the bearing. Remove the bearings and check their condition.

Oil leaks

• Damaged differential seals.

Brake system

Note. Before concluding that there is a problem with the braking system, check that the tires are in good condition and inflated to the correct pressure, that the front wheel alignment is not out of alignment, and that the vehicle is not loaded unevenly.

Increased brake pedal travel

• The working circuit of the brake path is damaged - check the system for leaks.

Brake pedal springs and falls

• Air got into the brake path - bleed the system.
• The fluid level in the GTZ tank has dropped, - make adjustments, bleed the system.
• The formation of steam bubbles. It appears mainly when the brakes are heavily loaded. Change the brake fluid, remove air from the system.

Decreased braking effect, pedal fails

• The tightness of the hydraulic path is broken.
• Cuffs in the main or working brake cylinders are damaged.
• Rubber gasket damaged. Repair the caliper.

Poor braking despite high pedal pressure

• Oiled brake pads.
• Incorrect or hardened pads installed.
• The brake booster is faulty.
• Worn brake pads.

Vehicle pulls to one side when braking

• Tire inflation pressure not correct.
• Protectors unevenly worn.
• Oiled brake pads.
• Different brake pads are installed on the same axle.
• Excessively worn brake pads.
• The caliper shafts are dirty.
• Calipers are damaged by corrosion - replace.
• Pads worn unevenly.

Spontaneous braking

• Clogged compensation hole in the brake master cylinder (GTZ).
• Insufficient clearance between drive rod and GTZ piston.

Brakes get very hot while driving

• The compensation hole in the main brake cylinder is clogged.
• Insufficient clearance between drive rod and GTZ piston.

The brakes are shaking

• Wrong pads installed.
• The brake disc is corroded in places.
• Excessive brake disc runout.

Brake pads do not move away from the brake disc, the wheel is difficult to turn by hand

• Corrosion in brake caliper cylinders. Repair or replace the caliper.

Uneven pad wear

• Incorrect pads installed. Replace pads.
• Calipers are damaged by corrosion - replace.
• The piston is difficult to move.
• The tightness of the path of the brake system is broken.

Wedge-shaped brake pad wear

• The brake disc does not rotate parallel to the caliper.
• Calipers are damaged by corrosion - replace.
• Piston malfunction.

Screeching brakes

• Often due to atmospheric influence (air humidity). If a creak appears after a long stay in high humidity and then disappears, nothing needs to be done.
• Incorrect pads installed.
• The brake disc does not rotate parallel to the caliper.
• The caliper shaft is dirty.
• Pad springs bent.
• Stretched compression springs.

Pulsation of the brake pedal

• A sign of normal ABS operation.
• Excessive brake disc runout.
• The brake disc does not rotate parallel to the caliper.

The ABS warning light comes on while driving

• Insufficient supply voltage (below 10 V). Check voltage. Check if the generator control lamp goes out after starting the engine. If everything is in order, check the alternator drive belt.
• There is a malfunction of the ABS, - check the condition and reliability of the fixing of the terminal connection of the ground of the return pump (in hydromodulator).

Suspension and steering

Vehicle pulls to one side when moving

• Tires unevenly inflated.
• Tires are defective.
• Suspension or steering components are excessively worn.
• Front wheel alignment required.
• The front brakes are stuck.

There are jerks, jerks or vibrations

• The wheels are out of balance or the discs are out of shape.
• Worn wheel bearings, loose torque or misadjustment.
• Worn or damaged shock absorbers or other suspension components.

There is excessive rocking of the vehicle/ «burying» his nose when cornering or braking

• Suspension struts are faulty.
• Damaged suspension components.

Steering wheel too tight

• The power steering does not develop the required power.
• Tires incorrectly inflated.
• Insufficiently lubricated steering gear joints.
• The adjustment of the angles of installation of the front wheels is broken.

There is excessive steering play

• The tightening force of the front wheel bearings has weakened.
• Suspension or steering components are excessively worn.

Excessive tread wear (not in one area)

• Tires incorrectly inflated.
• Wheel balance out of alignment.
• Damaged wheel rims.
• Suspension or steering components are excessively worn.

Excessive tread wear on outer edge

• Tires incorrectly inflated.
• Too sharp turns.
• Adjustment of angles of installation of forward wheels is broken (excessive convergence).
• Bent or twisted suspension arm.

Excessive tread wear on the inside edge

• Tires incorrectly inflated.
• Adjustment of angles of installation of forward wheels is broken (divergence).
• Steering components damaged or loose.

There is localized tread wear

• Wheel balance out of alignment.
• Damaged or bent discs.
• Tires are defective.

Wiper blade defects

Slippage

• Rubber working elements are dirty.
• The edges of the brushes are frayed, the rubber working elements are worn or torn.

In the cleaning field, the remaining water immediately collects in drops

• The windshield is dirty with lacquer polish or oil.

The brush cleans one-sidedly - one side is good, the other is not

• The rubber working element has one-sided wear.
• The wiper arm is twisted, the blade does not fit exactly on the glass.

Uncleaned surfaces

• The reliability of fixing the working element in the brush frame is broken.
• The brush does not adhere to the glass evenly.
• Lever pressure too low - lightly lubricate wiper arm pivots and springs or install a new arm.

Tire defects

Heavy tire wear on both sides of the running surface

• Tire pressure too low.

Strong tire wear in the middle of the working surface around the entire circumference of the tread

• Too high tire pressure.

Uneven tread wear

• Static and dynamic imbalance of the wheel, possibly due to excessive lateral runout of the disc, too much play in the bearing joints.

Uneven wear in the middle of the tread

• Static wheel imbalance, possibly due to excessive vertical runout.

Strong wear of individual sections in the middle of the tread working surface

• The result of hard braking.

Sawtooth tread wear, often along with an invisible tear in the tire's fabric base

• Vehicle overload. Check the condition of the inner walls of the tires.

Rubber tabs on the side edges of the tread (scaly wear)

• Wheel alignment out of alignment.
• Tires worn out.
• Defective shock absorbers / rack assemblies.

Burr formation on one side of the front wheel tread

• Wheel alignment out of alignment.
• Tires worn out.
• Frequent movement on undulating surfaces. Fast cornering.

Cord breaks. At first visible only from the inside

• Driving over sharp rocks, tire bumps, etc. at high speed.

One-sided wear of the working surface of the tread

• Check camber adjustment.
• There is a malfunction of the ABS, - check the condition and reliability of the fixing of the terminal connection of the ground of the return pump (in hydromodulator).