seeking Help with HID Diagnosis

[Lee Levitt]

Greville,

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Best,

Lee
Webmaster, SwedishBricks

Greville Bowles writes:

My Audi's all have halogen headlights. The help I'm looking for is for the wife's Volvo, so NAC here.

A while back the 2004 XC70 began showing the "bulb failure, low beam" error message on the dash. The driver side headlight was out. My immediate thought was, "Oh oh, it's a $150 bulb problem". Then the message disappeared and the bulb was working.

I haven't found any pattern to it, but every so often the bulb goes out and the message re-appears. Eventually it will come back on and resume normal operation. I have found that if I shut down and re-start when the error appears everything returns to normal, for  while. This is beginning to sound like Windoze, don't you think.

My experience with HID is zero so I hope someone here can shed so light on what is going on. Do I just replace the lamps and hope that's the problem? (With halogens that's what I'd do and it would cost me $25.) There are other (costly) components that could be the problem, so trial&  error could get expensive. I haven't found much info on HID diagnosis other than "check the connections for corrosion" which is what I plan to do next.

Any advice is appreciated. TIA