Xenon troubles, help!

[wuta3]

Hi All,

Just got the car back from an MOT and service with vag technik in Manchester (Who were amazing!) clean bill of health except for a headlight problem that has been doing my head in for a while...

Under hard acceleration or going over a bump, one or the other headlight will cut out and the dash will display the warning for the appropriate light. There's often a slight flicker before it goes out. Sometimes it is one, sometimes both. It appears to be a short as if I turn the headlights off and on again they immediately start functioning. Technik informed me of a "ground to live" short stored in the fault logs. It is often worse after heavy rain which makes me suspect water ingress.

Bottom line, I don't really want to replace the ballasts, what else can I do?

 

[NHN]

You need to eliminate 1st buddy, swap bulbs round, swap ballasts, then go from there.

 

[wuta3]

You need to eliminate 1st buddy, swap bulbs round, swap ballasts, then go from there.

Yeah they both are doing the same thing with the same frequency so not sure i'd gain ... i'd have to acquire some ballasts that were known good I suppose. The connector might be corroded though?

 

[NHN]

Both, it would be very unusual for both ballasts to do this at the sane time tbh, bulbs maybe, but one can affect the other that I've seen before, but you do need to eliminate.

Does just the xenon bulb stop or the whole headlights, just for clarity.

 

[wuta3]

Both, it would be very unusual for both ballasts to do this at the sane time tbh, bulbs maybe, but one can affect the other that I've seen before, but you do need to eliminate.

Does just the xenon bulb stop or the whole headlights, just for clarity.

The DRL stays on, seems to be just the Xenon. It feels water related given the rain thing and the bumps/acceleration triggering the short. Are they disassemble-able to try and dry them out? I have no idea

 

[NHN]

Yes but its a case of why they're getting wet, find the reason 1st before frying replacements, assuming all seals are in place behind the bulb carriers.

 

[wuta3]

Yes but its a case of why they're getting wet, find the reason 1st before frying replacements, assuming all seals are in place behind the bulb carriers.

Cheers, i'll have a proper look again tomorrow for any obvious signs of water or lack of sealage. I remember a while ago double checking some work done at a dodgy MOT place and finding the rear flap things ajar. Either way, the short is being caught and the bulbs seem to be OK.

I sort of hoped it'd be a common issue