10 replies to this topic

[chadd123]

I,ve just wired up my clubman estate rear lights
indicators work
hazzards work
brake lights work
BUT
when i switch the lights on with ignition off the headlights come on but the rear dont
when i turn the ignition on the rear come on
if i switch the lights off with ignition on the rears stay on the fronts dont
i,ve tried numerous wire swapping but i cant get it right
HELP PLZ

[Mervyn]

Did it work before? Sounds like the sidelight and dipped beam wires are mixed up at headlamp or switch, but could also be an earthing fault at the rear lights

Edited by Mervyn, 23 June 2017 - 07:45 AM.

[chadd123]

Just realised i,ve got no side lights either
checked earths,both headlamp and switch have original block connecters on
confused

[tiger99]

First, you seem to have a feed into the lighting system from the ignition switch. That is not normal, so we can assume it is due to a fault or crossed wire, as the car was not built like that. The indicators work so we can probably rule them out. The ignition switch energises the brake light switch, which has been known to short, so that provides a possible feed point into the lighting system. Also, it feeds the reverse light switch. Does the reverse light work normally?

 

I suspect that there are multiple faults, as no single fault could account for all the symptoms. Not uncommon, or expensive, just annoyingly difficult to fathom out. Possibly the brake switch has shorted (or just badly adjusted, it is press to open, pedal up) and the ignition feeds the brake lights which have no earth so the current goes back through the tail lights to earth through the head/side lights, but that does not precisely account for the symptoms.

 

There is not going to be an instant diagnosis on this one. The best way forward is to disconnect all front lights at the bullet connectors behind the bonnet catch, and all rear lights at the bullet connectors in the boot. Do not disconnect the black fuel tank earth. Disconnect the brake light switch. Then put the rear light cluster earths (black) back in, ensuring that they are clean, and the side/tail, which will be red. Try the lights and report back, or if ok, put the next thing in which should be the brake lights (green/pink). Continue until you find something that does not work.

[chadd123]

cheers i will try all that tomorrow

[mini-mad-mark]

Hi Chadd,

Are you talking about the minus maxi - maybe something missing with the earth at the rear of the car when you changed the lights

Regards

[chadd123]

Hi Chadd,
Are you talking about the minus maxi - maybe something missing with the earth at the rear of the car when you changed the lights
Regards

yes its the minus
i,ve got on rear lights r/h
red/black
white/green
green/purple
red/yellow
same on l/h
but a black aswell
then spliced out the middle of loom connect r/h l/h
i have a black which goes to into a red/white which goes to heated screen
and a yellow which goes intored/green which goes to back light

[chadd123]

Connecte one earth from each rear light
connected the red sidelight wires switched on lights,nothing
switched ignition on and i have rear lights
but if i then switch of lights rears stay on until i turn ignition off

[tiger99]

I never realised that it was a GRP bodied  car. That makes it interesting! No conductive bodyshell.

 

Where are the earths all connected?

[chadd123]

Too a strip of metal that goes across the boot of the car,the neg battery lead is connected too it

[tiger99]

That is about what I would reasonably expect. And at the front? Same sort of thing with a thick return wire to the battery?

It does sort of seem like missing earths and sneak circuits but the evidence so far is inconclusive. Maybe go visually through the harness, checking that the correct colour of wire is on each terminal?