Headlamps have come on by themselves and wont switch off!!??

[MPETT]

Hey Guys, I need some electrical advice please......
I walked back into the garage this afternoon, having washed the car this morning, and the dipped beams were on. I didn't remember having put them on and upon inspection, the switch was pointing to off?!

I thought maybe it was a relay that had got some water on it, so I played around with the switches going from off to dipped and flicking the high beams on and off. During the flicking of switches, the dipped beam turned off when I switched on the high beams, and sometimes when I used the flasher. So having got them to turn off (all headlamps off), I walked away to do the job I had come into the garage to do, then I turned round and they were back on again.

I identified the dipped beam relay and removed it. It appeared dry and I swapped it with the horn relay. SAME THING happened! The dipped beam was on again!

So now I'm wondering what could have got wet in the wings to allow the dipped beam headlamps to come on when the ignition is off??

Any ideas? I've pulled the relay out to save the battery and just in case there is a short. Should I disconnect the battery? I wish I'd fitted the kill switch in the engine bay! (got a bonnet conversion)

Cheers for your advice.

Martin

[R7EBO]

What year is it? I may be barking up the wrong tree but I've had all sorts of weird goings on with my lights in the past but they were all down to the dash pod itself. I had it refurbeb in the end & haven't had a single issue since. Might be worth having a look inside & giving it a waggle?!

[MPETT]

R7EBO said:

What year is it? I may be barking up the wrong tree but I've had all sorts of weird goings on with my lights in the past but they were all down to the dash pod itself. I had it refurbeb in the end & haven't had a single issue since. Might be worth having a look inside & giving it a waggle?!

Hi R7EBO,

Its an idea. I'll try wiggling the switch. The dash does sometime come up as 0000000miles, but its fine upon turning the key through all the positions again. My Air temp sensor is all over the place too, and that was a new part!

Cheers,
Martin

[MPETT]

MPETT said:

Hi R7EBO,

Its an idea. I'll try wiggling the switch. The dash does sometime come up as 0000000miles, but its fine upon turning the key through all the positions again. My Air temp sensor is all over the place too, and that was a new part!

Cheers,
Martin

Nope, that's not it. The tail lamps are working correctly and the back lighting on the mirror control switch is fine, so I think the pod is working fine. Some how the dipped beam circuit is getting a feed?

Martin

[MPETT]

The following day I put the relay back in and the headlamps came back on. I fiddled with the high beam and they went off and seemed to be working fine now. I've swapped the relay for the dipped beam with the hi beam relay and Ill have to see how it goes.
I got some advice from Paul smith that it sounding like the problem could only originate from the fuse board and could be water getting where it shouldn't. I had a good root around using my iPhone camera and it looks dry as a bone, so I had to assume it was a faulty relay.

[nawarne]

MPETT said:

The following day I put the relay back in and the headlamps came back on. I fiddled with the high beam and they went off and seemed to be working fine now. I've swapped the relay for the dipped beam with the hi beam relay and Ill have to see how it goes.
I got some advice from Paul smith that it sounding like the problem could only originate from the fuse board and could be water getting where it shouldn't. I had a good root around using my iPhone camera and it looks dry as a bone, so I had to assume it was a faulty relay.

Morning Martin!
Paul is a very helpful guy. He sorted my wing mirror 'control pad' for me.

I guess you've got a few 'steers' from Paul now. One thing would say is that I've known for the light switch to be temperamental on a mate's Tuscan....Just a thought.
Nick

[chimyellow]

I had a problems its mine the other days I the lights.
The symptoms were that they were intermittNt and the fog light did not work.

In my case it turned out they where the ribbon cable joined the back of the small circuit board which the rotary switch and button for the for light are on had a couple of broken wires. The other wires were holding it close enough for it to work most of the time.
It was just a case of removing the board cutting back the ribbon cable and re-soldering it back on.

[MPETT]

So the issue has come back....... Straight after washing he car! I had swapped the relays sontheyvTe not the source of the problem. There is water getting into the mirror control switch because the seal isn't that good, so in wondering if there is a link to the headlamps coming on? I need to consult with Paul again!

[nrick]

Martin

Have you had the fuseboard out to check for corrosion? Has to be on either the switch side (pod), the relay or the fuseboard itself?

[TucsanY]

What was the end result here... just had the same thing happen to me over the weekend. Any help appreciated.

Y Reg Mk1 Tuscan..

[QBee]

Could the car be a typical teenage male? Totally averse to any immersion in soapy water? And trying to tell you?

[Speed 3]

How bizarre, just had a call off SWMBO to say mine's doing this on the drive. I had a non-start problem a little while back which was a corroded starter relay. They suspected water ingress or condensation on the fuse board so maybe the two are linked. I forgot to put the cover on it on Sunday and we had torrential rain and wind overnight. Will have a mooch on Friday.

Edited by Speed 3 on Tuesday 2nd June 19:28

[Billiam]

Had the exact same problem on my 2001 Tuscan S recently and if i were a betting man, i would say water ingress if your lucky a good dry out will sort it, my issue was my boot which was ummm.. half full of water *shame face*

[TucsanY]

Dried the car out and yes the lights are back to normal... Bit concerning though that my British car doesnt like a little bit of wet stuff Will try and trace the problem back to an area when I wash it next. Has anyone got any pointers for how water can get to the fuse board?

[MPETT]

I put some more sealant between the scuttle and the windscreen and so far, even after a very wet day in Wales, I've not had any more electrical issues.

[Speed 3]

Mine has dried out and the problem went away. Main suspects for water ingress would be windscreen bonding and scuttle join. Previous owner of mine had a new fuse board fitted so I suspect its an original build issue. None of us that have tried can actually see it tracking though. I now keep a chemical dehumidifier (Unibond 360) in the footwell when not in use. Also need to be a bit more religious about fittting the cover.

[QBee]

The last point.......my Chimaera is a lot happier if I cover just the hood, glass and just in front of the screen. No more soggy cold wet ankles after a night of monsoon.

[TucsanY]

Thank you for the advice

[The Surveyor]

As quite a left-field suggestion, do you have a battery conditioner connected when you are having these relay issues? As in, are you washing the car then putting it away and connecting the battery conditioner.

I'm saying this as this happens on my old Maserati, but not on my Tuscan. When the conditioner is connected, there appears to be a small current flowing through the charger to both sides of the battery, and this stops the headlight relay shutting off once the lights are switched off. Disconnect the charger and all is back to normal.

Just a thought!