C

CP25

New Member
So my fog light stays on when the headlights are switched on

The light on the dash for the fog light illuminates as and when it likes!

Same dash light also illuminates when I go into reverse!

The only thing I have done is replaced the on/off switch for good measure.

Please help me my head hurts :emps1:
 
Sounds like a wiring bodge, or a problem in the wiring behind the dash/switch.
You really need the manual to get the wiring colours.
The lights switch should only provide power to the fog light switch when the headlights are on, so that is happening OK. But your fog light switch is not breaking the circuit.
Take the fog light switch out again, disconnect all the wires and put your headlights on. If the fog light doesn't come on, the problem has to be with the wiring at the switch. At a guess, I'd say the +ve feed to the fog light is on the wrong terminal.
If all else fails, I'm in Belfast too, and doing my head gasket tomorrow, so I'll be about all day.
 
To be honest it's been this way from I bought it so maybe someone has made a mistake behind the dash. Suppose there's nothing else to do but pull it out and have a look!

Anyone kind enough to have a wiring diagram? :confused:
 
The fog light circuit is slightly more complicated than it really needs to be but:

Light switch (off/side/main) is fed by permanent live from battery. In main light position it takes the Blue wire to live which in turn is connected to the input of the rear fog light relay. When the ignition is ON the rear light relay is switched on also and passes a live connection through to the output of this relay. This in turn feeds (fuse 6) which passes the current through to the fog light switch (using the Blue/purple wire) which when completes the circuit and lights the rear fogs and dash mounted fog warning lights (via the red/yellow wire). The output of the rear light relay also switches on the “rear fog inhibit relay” which passes a permanent live connection through to the input horn/direction/headlight/dip switch which in turn outputs either UW (main beam) or UR (dip beam) wires which then feed fuses 9/10 and fuses 7/8 to power the bulbs.

This sounds like something has shorted out or a connection has broken. From the description above you should be able to trace it.... Do you have a wiring diagram?
 
something like this?
RearFogLampsCircuit.jpg
 
Thanks for all the assistance guys.

When the main lights are switched on the fog light will switch on regardless of the position of the ignition barrel

It will also remain on with the fog light switch disconnected
 
CP25 said:
Thanks for all the assistance guys.

When the main lights are switched on the fog light will switch on regardless of the position of the ignition barrel

It will also remain on with the fog light switch disconnected
Click to expand...

Sounds like the fog inhibit relay is fused ON permanently. This could be a faulty relay OR it could be that the ignition live that should be going to the relay is shorted with a permanent live.
 
When I remove fuse 6 the fog light stays on and if I remove the relay it also stays on!

The only thing affected by the fuse and relay being removed is the illumination of the instrument warning lamp when the fog light switch is in the on position.
 
CP25 said:
When I remove fuse 6 the fog light stays on and if I remove the relay it also stays on!

The only thing affected by the fuse and relay being removed is the illumination of the instrument warning lamp when the fog light switch is in the on position.
Click to expand...

The fuse numbers might be wrong due to the way I created my diagram but what you could do is put everything back together and remove every fuse one after the other and see which ones stop the fog light (might be more than one). It is an easy fix to just chop wires and create your own fog light circuit but we can probably sort this remotely with a few checks :D
 
cowasaki said:
Sounds like the fog inhibit relay is fused ON permanently. This could be a faulty relay OR it could be that the ignition live that should be going to the relay is shorted with a permanent live.
Click to expand...

Thanks, where would I find this relay for a look see?
 
This is technically a bodge but WILL work (it is drawing the current for the fog light from the ignition live circuit which is fine for a single fog light)

If it is then you could get round it by chopping the two wires to the fog light switch and creating your own fog light circuit:

altfog.png


chop the two wires too the fog light switch
connect one of these to side light live
connect other one to 86 on relay
connect 85 on relay to ground
connect 30 on relay to ignition live
cut connection to the fog light lamp
connect 87 to the fog light lamp
make sure that the fog light lamp is grounding
 
Last edited:
Unfortunately not! The hazard switch (new) shorts the indicators out and the fog lights dead too!!
 
No I disconnected the hazard switch and it did nothing different with the fog. it's beginning to feel like a dash out rewire job!
 
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