Headlights on constantly

[PanoYeti]

Hi, have a 170 yeti elegance 62 plate that I’ve just had a sunroof leak in. I haven’t had any warning messages (that I know of) but whilst working on the sunroof one day I accidentally left the key in the ignition, on at first turn. Flattened the battery but got it going again and recharged fine.

 

Now, the headlights come on even when in 0 position and although the light switch is lit up it doesn’t seem to work. Also, when I turn the light switch and pull to activate fogs nothing happens. The fogs do work (reverse and cornering lights).

 

Had the flattened battery reset something and what are my options?

 

thanks 

[Frenchtone]

I had similar problems, the cause was a burned out/broken track on the pcb mounted in the rear of the switch, I replaced the switch  and then opened up the original to find the track problem, soldered a piece of fine wire to jump the burnt track, and the switch now works as it should, I think quality control in the Spanish electronics factory is a little lax, think the etching was not good or the pcb was in the etch solution for too long,  reducing the track width and hence the power carrying capability!

If you're not happy soldering etc switches from Tourans will fit and the tracking is more robust, try fleabay! you may have to transfer the bezel though!

[bspman]

Where did the sunroof leak to? Recently had a leak in my mm1 octy and the water came in through the bonnet cable release. This leaked into my light switch and caused it to short out.

 

I removed the switch, stripped it down and gave it a good clean but there was some corrosion.

 

Try removing the light switch and stripping it down to inspect it?

 

 

[PanoYeti]

Hi guys, thanks both for your responses.

 

bspman - leak ran down drivers a pillar, and into footwell via the thick mass of cables (sorry for lack of better description). See photos.

 

ive also removed the board from the switch. I’m no expert but it doesn’t look fried and certainly doesn’t look like any water damage.

 

i wondered whether there was a factory default the car had fallen into since the battery went dead.

 

tried the car without the unit connected and it doesn’t change the issue so guess that points to the switch??

 

[john999boy]

Duplicate topics merged.......

[PanoYeti]

Sorry mate - wasn’t sure how to delete first one

[Frenchtone]

mine was burned under the10 pin plug - one track passes between the 2 banks of pins, that was my prob! have you got a multimeter to check the tracks from the pins to the solder discs?

[PanoYeti]

I might have somewhere but I’m not sure what I’d be doing. I’m useless with electronics! If I can find the mm, where do I test and how?

 

sorry...  :-(

[PanoYeti]

I can’t help thinking I’ve done something whilst I was diagnosing the leak! I usually keep lights on Auto and I don’t remember having the lights come on during the day before the leak. Would keeping the ignition on for a couple of hours cause a problem in the light switch? Any other “obvious” things I’m missing? No cables that might be disconnected?

 

also, French, those connections are so small on the pcb. I’ll likely do more harm than good. I’d just like to be sure it’s the board before I go looking for a new one

[PanoYeti]

On 4/12/2018 at 19:16, Frenchtone said:

mine was burned under the10 pin plug - one track passes between the 2 banks of pins, that was my prob! have you got a multimeter to check the tracks from the pins to the solder discs?

What is the route of the electrical flow? I was able to test connectivity from the pins to the pads (that swivel and contain the metal pronged-heads).

 

if 1 track burns out does it automatically throw up an error and revert to safe mode for headlights? (At least that’s what I’m calling the mode I’m in!)

[Urrell]

1 hour ago, PanoYeti said:

if 1 track burns out does it automatically throw up an error and revert to safe mode for headlights? (At least that’s what I’m calling the mode I’m in!)

I do believe if there is a problem that is the "Safe Mode"

[Frenchtone]

Ok sorry about delay , I was up the other end of Brittany yesterday!

 

I attach 2 scans , one of the wiring to the switch and the other the pin numbering orientation - from that you should be able to assign pins on the pcb, what are the tracks like on the other side of the board? if the track has failed under the plastic of the socket base , with a gentle heat source it is possible to ease up the plastic and remove to view the tracks, you can then trace the track. if you attempt a repair use a low wattage iron and fine wire, its easier to solder on the underside of the socket and notch the board edge to get the wire run up to the pad.

If the light switch has a problem of electrical supply it defaults to permanently on, ie when ignition switched on lights on as well, with control of main beam, dip, fogs etc a safety feature so the car is useable at night .

Edited 14 April, 2018 by Frenchtone

[PanoYeti]

Hi French, thanks for your response. The diagram isn’t clear enough for me to follow it but even if it was I’m not sure I’d understand it!

 

I tested each pin to see if it led to somewhere. Pins 3,4,6 and 10 didn’t appear to “reach” anywhere (I was trying to see if it would run to the curved pad). 

 

My best next step is to try a working switch in the car to see what happens. Do all yetis of the same age range use the same switch? I might go hunting yeti drivers...

[Frenchtone]

yeap all have the same switch as do other vw/audi etc of similar age, just need to check the plug socket, as some are different  -  I added some more to the last posting I made. if you want a bigger image, pm me and i'll try to send you one!

 

[PanoYeti]

Great, image is perfect now.

 

all of the lights work (that I know of) I just can’t control them using the switch. The coming home feature doesn’t work anymore - would that be because of an electrical problem?

[Frenchtone]

no idea on my 'simple' manual system the track to pin 1 seems to control everything - may be to the coming home feature which I do not have as well, the switch is relatively low amperage and it connects to a control box which I am lead to believe uses relay? or switching transistors(I do not know never had to get that far)

as previously all my lights switched on when the ignition switch was turned to the run position, even without the switch attached, I think it is a safety / get you home feature / situation if you get 'stranded' after dark!

[PanoYeti]

Thanks French, I tried my car at night and all the leds were lit around the switch - does this prove an electrical supply to the switch?

 

i noticed the current Tiguan model has the same switch by appearance but wasn’t sure if I’d blow something if I tried to connect it

[Frenchtone]

supply to switch lamps yes  but not an indication of switch power ie when the dash panel illuminated all other switches etc are also. if the plug socket on the rear is the same as the yeti then it should work. If you get a tiguan switch you will probably have to transfer the front bezel from theyeti job to the tiguan as different pieces were used to accommodate dash contours etc

[PanoYeti]

So although the leds lightup at night around the switch this doesn’t indicate the switch is getting power? 

 

The cable connector that plugs into the switch - does this connect to another socket just behind the dash trim? I’m still thinking I’ve accidentally disconnected something whilst “tinkering”

[Frenchtone]

no x2