Dec 24
Dashboard Warning Lights
Dashboard warning and malfunction indicator lights
Engine management / emissions defect warning light
This indicates an Engine Management System malfunction on either gas or diesel vehicles. This relates to emissions of the car. When the light is on, you can drive the vehicle to the repairing garage. This indicates a "fault code" and should be checked with a scan tool prior to driving. The lamp may be on all the time or flashing a manufacturers specific functionality. The diagnosis once scanned will tell us, the length of time that the MIL (manufactures indicator light) has been on. Failing to repair this emission trouble in a timely manor may cause further damage, most likely to the catalytic convertor.
Engine Management fault warning defect
This is an alternative lamp to the one shown above and has identical functionality.
Glowplugs on (lit) Engine management defect(flashing) warning light
This lamp is specific to diesel engines only. The glowplug light will illuminate when the glowplugs are operating. This is normally prior to startup on a cold engine. If the engine is struggling to start from cold and the lamp does not illuminate when the ignition is first switched on then there could be a fault with the glowplug system.
On some manufacturer's systems the glowplug lamp has further functionality and if permanently illuminated or flashing then this indicates a diesel fuel injection fault.
A third function on some VAG vehicles is when lit in conjunction with the diesel particulate filter warning lamp indicates the condition of the filter.
Anti-lock braking system (ABS) defect warring light
This indicates a malfunction in the ABS system. When this light is on, braking conditions for the brake system will revert back to conventional braking and the anti-skid function will not work. As long as no other lights lamps are on, it is usually safe to drive to drive to the repair shop. With all indicator lamps, the brake system is not different. We use a special scan tool to check and evaluate the brake system. This will give us the "fault code" and data we need to diagnosis, repair and reset the system.
If a vehicle is presented for an MOT test with the lamp on permanently , or not working the right way, when the ignition is turned on and the vehicle performs a functionality test prior to turning off the light, then the vehicle will fail the MOT test .
The repair shop will have data that informs the tech when the light should go out. All cars are different and data must be read according to the different vehicle manufacturers.
Electronic stability program (EPS) defect warning light
The EPS lamp may flash when the system is in operation (wheel spin / skid prevention). If the lamp stays while the car is driving this indicates that the driver has manually turned the system off or there is a fault in the system. The vehicle can be driven to the nearest repair station for diagnostics.
Airbag or belt tensioner system defect warning light
This lamp indicates that there is a fault in either an air bag or a seat belt tensioner, (before taking the vehicle to a repairer ensure that this is not indicating that the vehicle owner has turned off the passenger air bag to fit a child seat as sometimes this lamp will also indicate this). Should the lamp stay lit once the vehicle is moving then the vehicle needs to be checked with the necessary diagnostic equipment.
Unlike the ABS fault warning light, the SRS light is not part of the MOT test. The tester may however advise the customer that a fault exists and should be rectified as soon as practicable.
Electro-mechanical steering system defect warning light
This lamp indicates a fault in the electro-mechanical assisted steering system. The steering may become very heavy and the driver may struggle to turn the steering wheel comfortably and thus require the vehicle to be recovered into a repairer. As with most systems an intermittent fault may be reset by turning off the vehicle and restarting it; although this will still need to be checked to prevent future breakdowns. On some systems it may also be worth checking the power steering hydraulic fluid level.
Diesel particulate filter system defect warning light
This symbol indicates a fault on the diesel particulate filter. This filter removes particles of ?oot' from the exhaust emissions and is prone to become blocked / partially blocked if the vehicle is used on short runs. If the light comes on and stays on then it may be possible to ?egenerate' the filter by driving the vehicle at a preset speed / engine revs as per the manufacturer's handbook instructions. If this lamp fails to go out after a drive cycle then take the vehicle immediately to a repairer to diagnose the fault as leaving the vehicle in this state will invariable put the vehicle into a reduced power or no power state and require the vehicle to be recovered into the repairer.
VAG use the engine management warning light and the glowplug warning light in conjunction with the particulate filter light to highlight the level of blockage of the filter and whether the drive regeneration is possible or it needs to go to a vehicle repairer.
Immobiliser / key recognition system defect warning light
This indicates that either the chip within the key has not been recognized by the key reader or there is a fault with the key reader itself. Either way the vehicle will / may crank and fail to start or even fail to crank depending on the system; during the attempt to start the vehicle this symbol may stay illumined or flash. If the key has been dropped and come apart it is worth checking that the chip / transponder has been refitted into the key or try a spare key. Some VAG vehicles will start and run for a few seconds before cutting out if the key is not recognized. Re-synchronisation can occasionally be performed by leaving the ignition on for 10 minutes.
Any faults with this system will invariable require the vehicle to be recovered. Often due to the sensitive nature of this system only the main dealer can fix this system, although it is worth checking with independent diagnostic experts as well. Proof of ownership would be needed for this type of repair.
Alternator charging system defect warning light
Although this symbol represents a battery this light is for both the alternator and battery. When the ignition is switched on the light should illuminate and once the engine has started the light should go out. This indicates that the function of the warning light is working.
If the light stays on, this needs to be repaired as soon as possible. The car battery will discharge leading to a no-start or a car dying on the road. Other than checking any charging fuses, or visually checking the alternator drive belt, test equipment will be required to confirm the problem. Always check that the light comes on as soon as the ignition is switched on and goes off once the engine is running.
Engine oil pressure low warning light
This light should go out within a few seconds of the engine starting if not immediately. The light indicates that the oil pressure switch has not seen adequate oil pressure in the engine to put the dash board warning light out (or via ECM). The engine should be stopped right away and the oil level must be checked. If the level is low, add oil and re-start the engine; if the level is fine then you need to go to a repair shop to check the oil system.
NEVER drive with this light on. Some cars will not run with this light on, to prevent engine damage if there is not enough engine pressure.
Some systems have a separate light for oil pressure and oil level.
Coolant temperature too high warning light
This lamp indicated that the engine coolant temperature has is too high. Some cars have a gauge not a light. You must STOP your car as soon as possible when the gauge is too high or light is on.
NEVER check the coolant when the car is hot. You can wait to check the coolant level once the car has cooled down. Never release the radiator cap or overflow tank pressure when the engine is hot. This is very dangerous and could result in severe burns.
If the coolant level is low, temporally you can top off the fluid to get the car to the nearest repair station, to be checked.
Continuing to drive a car with a coolant leak or overheating engine can cause extensive / expensive damage to the engine.