Odd electrical issue - headlights

[Ghost]

Car has a HID upgrade installed by a well known indie probably around 10 years ago.

There has been an intermittent fault with the nearside driving light not coming on; I initially suspected it was the bulb, but it hasn't blown.

Last night, the problem transferred to the offside driving light.

If I switch the lights off and on again, there is a delay of a few seconds before both lights come on.

Interestingly, when this happens it causes the rev counter needle to spike and shoot round the dial and fall back again, although thankfully without the engine following suit.

No problems with the lights on full beam which are as Porsche originally intended.

Presumably something is shorting out somewhere, but any ideas where to look before I start trying to find a preferably mobile auto electrician?

Tia :thumb:

 

[jhrfc]

It could well be the HID ballasts, (esp if they are 10 years old) you could try swapping them over.

 

[wilsonny]

It could well be the HID ballasts, (esp if they are 10 years old) you could try swapping them over.

Definitely worth a try to eliminate, one of my ballasts went within 6 months, but it did fail completely rather than the symptoms described.

Obvious area to also check is the condition of the connector at the back of the headlights... They can get damaged as the headlights are put back in and could be cause of short circuit.