Plunged in to darkness at 70mph!

[alanstead]

I am just wondering has anyone else had or heard of a similar problem to this? I was travelling home the other night, cruising along at 70, and the headlights turned off. I started braking and a second or so later, they came back on again. Not nice and if I had been on a tight corner or in traffic it could have been a disaster.
My car is fitted with factory Xenons and I had the headlight switch in the auto position as I always do and I was on main beam. The lights were off for about two seconds, and then came back on, on dip and cycled through the up/down levelling that they do just like you had just turned them on. I have given the switch a good wiggle about and the wiring behind it, but I cant recreate this fault? What else may it be?

Anyone??

[ZephyR]

Wow! A bit worrying that.

[bitmadmax]

Get it to your dealer - if you have vagcom might be worth checking if there were any faults logged.

Did any of the dashboard/speedo etc lights go out as well did you notice?

[RW1]

Check the fuses are fully home and not loose. (Not expecting a blown fuse)

Engine Bay - Fuse 7 (40 amp (Orange)), Fuse 26 (30 Amp (Green) or 40 amp (Orange))
Driver's Side Dash - Fuse 1 (10 amps (Red))

C.

[alanstead]

Cheers for replies. I never noticed the dash lights to be honest! The Speedo was lit, but it comes on with the key. I will check fuses later and also stick the laptop on it to see if any faults logged. Fingers crossed its just a loose or dirty fuse connection!

[GiannisA]

I have the same problem with you. Having factory fitted xenons and with the lights in AUTO position, it happened to me 3-4 times in the last year, but for my good luck in all cases my car was stopped at the traffic lights.
For sure I can tell that all lights turned OFF for 1-2 sec, just like if I had put the lights switch to OFF. Every time that happened, I checked my car with VagCom but no faults were logged. Also never happened till now using lights switch in the ON position (instead of AUTO).
So, I believe that the problem has something to do with the RLS (Rain / Light Sensor) function. It seems like for some reason it feels for a while that the level of the external lighting is above its threshold, and turns off the lights. On the other hand as I wrote before, nothing in VagCom proves that the sensor has any problem…

[RW1]

I know GiannisA has done this in February 2012 and the problem has appeared.... Auto Light Sensitivity Adjustment
Alan, have you adjusted???

Which may mean the circumstances triggered the new threshold setting point.
It would explain the shut down and no fault. The sensor may have reacted to a main beam headlamp travelling in the opposite direction. Hence why 2 seconds later after the vehicle has passed, the headlights return.

Suggest the threshold is upped to more lighter twilight conditions where them going off will not be an alarming exprerience. Try replacing 0A with value 0F (10% to 15%). It will always happen as the circuit works on a sensor threshold detection point. You may need to adjust up more until oncoming headlights or street lamps are not prominant in the low light conditions to eliminate the influence on the Light Sensor.

C.

[GiannisA]

I totally agree with you RW1
And as you do remember very well, i changed my RLS sensitivity value to "0A" (10%).
You describe exactly all that i have in my mind about this "problem" !!!
Anyway I will try to change again the sensitivity value with “0F” (15%) and check how the sensor will react..

[alanstead]

Nice to hear someone else has suffered this problem. Yes I have adjusted the sensitivity, however, when this happened I was on a country road, no street lighting, no other cars anywhere, and no road signs that may have reflected my lights. Sounds as tho it must be a problem with adjusting the lights, but why now, and only once, I have no idea. I shall put in the suggested coding, and see if it happens again. Oddly, they have been adjusted since last summer because they were on nearly all the time, even on sunny days! But were notiecable in their absence on foggy days. Great idea, poorly executed! My dads Audi has auto lights and wipers, and its system is far superior to the system on my car sadly. VW had the car back after I got it because I was so annoyed with auto setting, but they said it was ok!
I have checked the fuses and vag com, but everything is ok.

I'll report back if it happens again, if I'm still here!!!