Headlights on when switched off

[cralittlewood]

Hi,

I originally had this problem over a year ago and at the time I removed the Headlight relay for 48 hours and then reconnected and it has been fine since.

However the problem has just started happening again, it is intermittenant. When I have the headlights turned off they just come on of their own accord, even without the iginition in. Whilst the headlights are on, if I turn the light switch to put the side lights on then the headlights go off and the side lights come on.
Last night I disconnected the Headlight relay so that it would not drain the batterys, but when I tried to start it this morning I just got a click.

I connected a booster charger and started the car then let it run for 20 minutes. The headlight relay is still disconnected. After 20 minutes I stopped the engine and the car started with its own batterys. I did notice that there seemed to be a lot of clicking going on under the bonnet for a few minutes after I turned the ignition off

I looked all around for something turned on that was taking charge from the batteries but all was turned off. I did notice that the airbag light on the dashboard was on all the time, this has only just started happening.

After 30 minutes I have just tried to start, and again and it is as dead as a dodo.

Both times this has happened in the past is shortly after the it has been parked up at an airport without use for 4 days, not sure if this is relevant.

Any help gratefully recieved.

[Medieval Dave]

When your headlights come on on thier own is it just the heads or do your taillights, no plate lights etc come on as well.

If so then proabably it's the light control switch itself falling apart inside.

If not I might be tempted to think that the loom has chaffed against a metal edge either near the steering column, or where it goes through the bulkhead. i would go round wiggling the loom and watch for lights going on/listen for clicks. you might want to have a pocket full of spare fuses.

Remember that all the light control relays are switched earth, so shorting wires to earth on a toymota tends to turn stuff on as often as blow fuses.

Also have a look at your foglight setup. depending how it's wired that could give a leakage current.

or it's haunted.

Dave

[cralittlewood]

Dave,

Thanks for the quick reply.

Just waiting for my mate to bring a battery charger round.
Will have a look at what you suggested tomorrow, I'm off to a beer festival this aft, don't know how I'll be able to enjoy myself knowing my baby's broken at home.

Craig

[surfcarl]

um, shot in the dark..... do your headlights flash when you arm your alarm ???
when parked for 4 days.... is alarm on ?? try dis-abling your alarm and see what happens ??? somewhere safe, of course.....
hope this may help...

carl....

[cralittlewood]

Headlights don't flash with the alarm.

Just re-connected the charged up battery's. The voltage on the batterys before connecting was 13.2V on one on 12.7 on the other, is the second voltage a bit low and does this indicate a faulty battery, it had been charged for 5 hours.

Started no problem and re-connected the head light relay but couldn't get the lights to come on when switched off as per before. Wiggled a few wires but couldn't get them to come on. I have left the relay in to see if the lights come on after a while, which is what was happening before.

Checked the voltage on the batterys whilst it was running and it was 13.6V on one batter and 13.69V on the other battery, does this indicate that the alternator is ok.

Cheers,

Craig

[cralittlewood]

Left the charged batterys overnight in the surf and there as dead as dodo now.

Connected my booster pack and there clicks all over underneath the bonnet.
wondering if one of the batterys is bad and is discharging the other.

Charging the batterys again now and will probably take to an auto electrician to have a look.

[Uplander]

Headlamps / sidelamps problems

Hi,
This is a very basic snag, needs sorting to avoid major snag...
One must assume the fuses for lights are functional. CHECK THEM...
Commence your wiring checks at the headlamps. Check each in turn, your seeking a broken or chafed cable or poor / dirty connection/s.
Check also the sidelight cables after the headlamps.
The relay needs to be checked - some on here maybe thinking its a prime suspect, could be ! Also is it fused - is this operating satisfactorily.
This snag could well be a poor earth on one or more of these parts. Question of isolating and then curing this...

If you turn up nothing after checking the above, then I would advise you go to auto electrician...Hope its an easy diy fix for you..

Peter

[sparkyaj]

A quick thought if your testing yourself to save you some dosh....

When I test 230/400V supplies for faults one of the first things I do is switch off power. - this case, discon batts.

Pull fuses - likewise, pull out as many fuses as poss.

Grab a multi meter and set to test continuity. if its a digital one you should see a 1 or 100.

when you hold the leads together it should drop to 0 - thus dead short.

Put the multi meter on continuity between the body of the truck and the lead you have disconected. NOT THE OTHER TERMINAL ON THE BAT OK!!


See if you get a 0 ohm reading. - by removing the fuses you should remove all loading and have a 1 ohm - thus all clear.

if you have a 0 at his point then you either have more fuses still connected OR if you sure to have pulled them all out, you've got a bad problem.

Put fuses back in one at a time re-testing until you get a dead short ie 0ohms

As long as you test only one fuse at a time you will be able to get a fault reading for every circuit that is still drawing power even with the ignition switched off.

For talk say, if both the lighting fuse and wiper fuses when in cause zero readings - it will give you a quick idea of which circuits to look closer into.


If that as clear as mud????? I hope not.

As long as you have a meter, should take you 10mins tops to fault find every circuit pulling load whilst all power is turned off.

Regards

sparkyaj