Hi,

 

 

I have a 2012 Yeti 170 4x4 Elegance with the automatic lighting function, hence my lighting switch has 4 positions; Off, Auto, Sidelights and Headlights, plus 2 pull positions for front and rear fog lights.

My headlights now come on regardless of switch position, as soon as the ignition is switched on.  The front and rear fog lights do not come on when the switch is operated.

 

Having read other threads, here and elsewhere, I replaced the switch last night.  On doing so, it operated correctly when the ignition was turned on.  However, as I dove to work this morning, I found that the fault had returned as before.

 

Assuming that the second switch is OK, (it worked initially), then some other components must be affecting the lights.  What would they be and where are they in the car?

 

My car has a panoramic sunroof and has had a minor leak in the past, although not currently, (as far as I can tell).  The lighting problem did not start until well after the leak was cured, so may not be related, (but then again…).

 

Advice from those who have experienced the same problem would be appreciated.

 

Thanks

 

Simon

2 tracks on the internal pcb may have burnt out, 2 options, find some fine wire and jump the missing bits or another oem switch, I think the cheaper varieties have a penny pinching thinning of the tracks, then, they cannot cope with the load

I replaced the switch last night with a genuine part from my local Skoda dealer.  As stated, it worked initially with the ignition on, but failed this morning with the engine on.

I would go and have a look at the light sensor - which is located up near the mirror.  If water has been leaking from the sunroof, you can bet there has been some hydroscopic leaching toward the loom of the sensor - and hence why it may have become a short and indicating to the car that lights are required on at all times.

 

Try and get the sunroof fixed first; then try drying out the car afterwards - easier if you have a garage....either heater or silicon bags to absorb any excess water.

Would a "call" from a sensor override a switch set to the off position and also prevent it switching other lights not governed by the sensor, I.e. fog lights?

The inability of either switch to turn on the foglights would suggest that this is either a switch (potentially ruled out) or module/wiring issue.

 

The BCM (Body Control Module) that controls the exterior lighting is located up off the floor above the driver's feet.

 

Where did the water from the sunroof leak track and pool?

Left front corner of sunroof, down left A pillar to front passenger footwell.  No pooling, so not a major leak.  No sign of a leak on driver's side; no damp carpet.

Not wishing to insult intelligence, but best to check fundamentals...

 

Are you 100% it's the headlights coming on - IE have you stood outside the car and seen them ?

(Making sure it's the headlights that are coming on, and not that you're seeing light from the DRLs illuminating the area in front of the car...)

Not insulted at all; it's easy to overlook the obvious.

Yes, it is the headlights.  I can see them "do the dance" when they come in and have confirmed by checking from outside the car