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I have a 2003 1.4 TDI SPORT and i have noticed when traveling especially at night with my lights on there is a click from under the dash (under the light switch area) and the lights dim for maybe only for a second and then come bright again like when you use something that uses alot of power it can do it a few times. I thought it might be the cooling fan but it does it mainly when the car is cold. My aircon is off too.

Any ones 9n do the same??

Also my brake lights kept sticking on and when i rattle the peddle they would go off. But tonight they finally dicied to stick on on! The glow plug light started flashing to warn me. It took me ages (in the local garage VERY imbarassing) to get them to go off. They are now off and the glow plug light has stopped. But it has left 2 fault codes (16955 brake light switch i know) but there is one i cant understand 17978.

Any ideas?? Many Thanks

17978 from what I've found on the net means The control module is locked. I would get the codes reset/erased and see if they come back as it could be something to do with the failed switch.

I'm sure mine makes the clicking as well

DGraham wrote:I have a 2003 1.4 TDI SPORT and i have noticed when traveling especially at night with my lights on there is a click from under the dash (under the light switch area) and the lights dim for maybe only for a second and then come bright again like when you use something that uses alot of power it can do it a few times. I thought it might be the cooling fan but it does it mainly when the car is cold. My aircon is off too.

Any ones 9n do the same??

that is quite normal behavior. its the glow plug relay working itsway through the cold weather, and it requires a large current to operate, hence the voltage drop that makes the lights dim.

hope this helps