glow plug warning light flashing on and off,took to garage for repair as brake lights where not working either.told that they had replaced brake light switch but had traced fault of glow plug warning light to coolant temp sensor.can this be right as i have had no trouble with the temp at all on this car.thanks for any help and advice.stallion66

ps it is a 2002 model octavia

Edited 19 September, 201015 yr by stallion66

Temp sensor is a common fault on VAG cars, but I have never had the glow plug light on as a result of it failing.

The failed brake light switch can cause the glowplug light to flash. The CTS failure make log a fault on the ECU, but I have never seen it cause the glowplug light to flash - I suspect the garage scanned the car for faults and picked up on the CTS giving dubious readings.

CTS & o-ring is about £20-£25 to replace, iirc, and takes literally seconds (any longer and you might need to top up the coolant if you allow enough to pour onto the ground!).

The failed brake light switch can cause the glowplug light to flash. The CTS failure make log a fault on the ECU, but I have never seen it cause the glowplug light to flash - I suspect the garage scanned the car for faults and picked up on the CTS giving dubious readings.

CTS & o-ring is about £20-£25 to replace, iirc, and takes literally seconds (any longer and you might need to top up the coolant if you allow enough to pour onto the ground!).

thanks mbames appreciate that, its just that i paid £139 for the job and the parts came to £38 but not having any trouble with the heating system i just could not understand the reason why they had to do anything with the cts,the parts £14 for brake light switch,£24 for switch ,does not mention what that was for except that it says check out glow plug warning light stays on checked out the glow plug warning light on the skoda octavia traced the fault to coolant temperature sensor for the engine management.as you can tell i am totally ignorant to what all this means i am just hoping that i have not been taken advantage of.anyway thanks again for your help its very much appreciated.

The CTS on the Octy has 2 feeds - one to the temp gauge on the dash, and a secondary feed to the ECU. This part of the system deals with removing the heat from the engine, rather than the warm air supplied to the cabin.

Costs of the parts sounds about right, so I am guessing you were charged for about an hour of labour (expensive garage at £100/hour), which sounds like it might be a bit on the steep side, but changing the brakelight switch can a bit of a PITA.

Get a shareware version of VAG-COM, it will pay for itself almost immediately, as you won't get stung for dealers saying "we just need to pop that onto the computer and check for error codes, oh and that will cost you £50 please :wonder: "

thanks for that Mbames you have been a big help,i am a lot more clued up than i was before.CHEERS.