Foglight help req.

[John]

I am sure I am missing the blindingly obvious, but as I am in a lot of pain (see choke saga) and full of Distalgesics, I throw myself before the collective brains trust that is Classic Rover for assistance and advice. I have recently wired in my Lucas Sq8's. Nearside works. Offside doesn't. With the switch OFF no power to live side (as it should be). Switch ON, test light shows power (to a remote earth). Multimeter shows 11.9v. Put an H3 bulb in the circuit, darkness. Check bulb across battery, lights up (blindingly :shock: ). Check earth lead from light to live, circuit lamp lights up. Put in together, darkness.
So in summary: I have a working bulb, I have power. I have an earth. I have darkness on the offside. Any clues would be appreciated. I am now going for a lie down in a dark quiet place. (in front of my o/s foglight!)
Cheers John.

 

[arthuy]

The wires can get stretched and damaged.

Repeat the tests you have done already but with the bulbs removed or disconnect the unit and use a meter to continuity check the wires. could even be a dirty bullet or snap connector.

Colin

 

[Dave3066]

Hi John

How have you wired them up. IIRC, and I'm doing this from memory so best to check, this is the wiring behind the glovebox for the lights:

The red/yellow is the power for the lights and the blue/yellow wires each feed one of the lights. Both of these need to connect to the red/yellow to get a supply to the lights, if you've only connected one that would explain why only one light comes on. It seems bizarre with there only being a single female connector on the red/yellow but I'm sure that's how it works. Then take the return from the lights themselves to an earth point.

I had a similar problem with my car when I got it as someone had wired the lights up completely wrong and my nearside fog light would come on when I braked :shock:

Have a look at your own car and check the wiring.

Dave

 

[John]

Hi guys thanks for the input,
Dave the wiring is correct as I searched the forum and found the pics of how to do it.
Colin, I think you've hit the nail on the head, whilst lieing on my back contemplating the ceiling I realised the only thing I didn't do was to isolate the actual wiring from the light unit to the cars loom. I am thinking I have a short, probably where it exits the light casing. Tomorrow I will run a test wire straight from the loom connector, if i get light I will rewire the actual light unit connections. If that fails I will go and lie down for another think!

 

[John]

And someone said "Let there be light, and there was light". Rewired the light units wiring, so the short must have been in there. I forgot the first rule of life, never assume anything!! (and always do continuity test on Lucas the Prince of Darkness products).
Towbar fitment next on the list.