Headlights wont turn off (re-visited)!

[diggerdigger]

Hi All,

My lights won't switch off when the engine is running

I think this hasn't helped the battery which was as flat as a pancake yesterday. I charged it up overnight, removed the cheap and cheerful headlight buzzer hack but still the headlights (and rear) stay on until the engine stops. I can't see how the headlight buzzer could have caused this but it can stay disconnected until everything starts behaving again....

I found an archive thread (called "Headlights wont turn off!!Hi") on what seems like the same fault - but it didn't seem to be resolved.

I know I need to check the earthing - but it's cold and rainy out there right now. I'll check the earths and the light switch when the weather is less grim - but anyone had this same problem?

[itchyfeet]

Have you tried changing the switch, sounds like it's broken in the on position, lights go off with ignition if left on.

[ELVIS]

Firstly, is it a Swedish/Scan import or is it a fault that's just started?

[diggerdigger]

It started recently - I think I would have noticed last winter if it was in 'Volvo' mode. Is that even configurable?

Update: Today I changed the headlamp switch for nice new one from justkampers - it was only about £10 including the postage, so I thought I might as well change it given that the switch was the chief suspect.
Anyway - no joy - problem still there. Nothing obvious when looking at the wiring in the fusebox area.

So, back to the wiring diagrams - now I remember why I'm a software engineer ...

[MidLifeCrisis]

Is it definitely headlights and not the highbeams?

[diggerdigger]

Definitely dipped headlights (waited for it to get dark to check )

[bigbadbob76]

Hi Digger.
Software drives me crazy, that's why I'm an electronics engineer.
if we work through this logically we'll find it.
I don't know how much you know so don't be offended if I ask simplified questions.
Need some more info first.

You say dipped headlights and tail lights stay on when engine is running but light switch is off.

1- do lights come on (with light switch off) when you turn ignition switch to acc but don't start the van? or does the engine have to be actually running?
2- have you, or a PO, done a relay mod to the headlights? (other than the buzzer)
3- when the lights are on (with the light switch off), do the main beams come on if you use the main/dip stalk?
4- if you unplug the light switch does the problem go away?
5- if you unplug fuses 21 and 22 do the lights go out?
6- if you unplug relay 8 does the problem go away?
7- if you have the resistors under your nearside headlamp, try disconnecting them, does the problem go away?

That'll give us a starter for 10. we can work from there.

[diggerdigger]

Sorted!

Thanks, bigbadbob, - for the action list. It's a nice sunny dry day today so I though I would work through the points one by one.

Disconnecting the light switch made no difference, and then while replacing the instrument cover, I noticed the switch in the foglamp position was on. Ah ha! I thought - switched it off - all back to normal

So, this must be the 'Volvo/Saab mode' switch? Always wondered what it's for. It's red with a single triangle - (don't think I had a switch in that position on my previous 1984 van). Not even sure I've got any fog lamps - I will investigate further.

So it was operator error - which is arguably a software error (or at least a user interface shorfall) - or maybe idiot operator scenario - It would be a stretch to blame it on the hardware.

Thanks again all.

I'm off to the tip now, with another van-load of crap to get rid of.

[bigbadbob76]

Sounds like the user was not informed of the beta version which resulted in an interface failure.
Also sounds like someone's been buggering about with your wiring.
Red with a triangle??? is that not the hazard switch, maybe someone's used a hazard switch as the "Volvo mode" switch.
Glad you got it sorted anyway Digger.