Couple of other Wiring Questions

[oli8925]

Fog lights...I've wired mine in as the Haynes diagrams told me to. Two wires from the fog switch go to 2 terminals on the bulkhead connector. 2 wires come from the same 2 terminals on the other side to the relevent fog lights. The switch is new and from a Mini and the wires are of the right gauge for the standard Lucas period lights. The light output has always been utter rubbish (I wasn't expecting great things but really...) and the last time I used them something started to smell funny and the lights went funny. I couldn't find any source of heat though or any obvious burning or damage to the loom or switch.

Does anyone have any ideas on the problem and would adding a relay between the switch and the two terminal on the bulkhead connector help with the problem or the light output do you think?


The other question is to do with the door switches which are purple/white wires on the loom. As I haven't stripped the loom yet I can't quite tell how it works. I take it the switches act as earths when they're extended (doors open). There are two purple/white wires going to the drivers door and one going to the passenger door, why are there two going to the drivers door? In order to fit switches to the rear doors, shall I just splice the length to the relevant rear door into the wire for the front door? Will I need to fit diodes to the circuit to stop the alarm tripping constantly?

Thanks for any answers.

[shamm]

The wire is a loop so two wires to go in-and-out and one wire the the end of the loop.
Just splice more switches into the same wire for rear doors.

[dann01]

Door switches run in line, not paralel.

To be frank, I'd wire and switch the fog lamps completely seperately from the cars existing loom, regardless of if there are wires there ready... The wires weren't up to much 30 or more years ago when put in, so several decades on, they probably ain't up to much still.

And a relay will help any light situation.

Dan

[oli8925]

Great stuff, thanks.

The wiring for the fogs is new last year, I did it myself and is fairly thick so should be ok, nor are the bulbs in it massive wattage. Where in the circuit should I add the relay, between switch and bulkhead connector or between connector and lamps? Although as far as I can work out it shouldn't make a difference as only the top row of the bulkhead connector is powered isn't it, the rest is literally just a connector? for the two looms. Just want to make sure before I cut the wires.

[shamm]

No, the door switches are wired in parallel, bulkhead to drivers door, then to passenger door, hence two wires at drivers door contact.

[dann01]

Think one of us is getting confused here Shamm... If door switches were run paralel, then there would only be one wire to the driver side... So they must run In line - as in xmas tree lights - on the earth side, surely?

Dan

[shamm]

It's done that way to save copper, rather than taking both switch back to the bulkhead connector.

[droopsnoot]

I think it's a terminology thing - they are wired in parallel, if they were in series then both doors would have to open before the light came on. But the in-line desciription makes some sense because of the physical layout of the wires, not the electrical layout.

Where in the circuit should I add the relay, between switch and bulkhead connector or between connector and lamps? Although as far as I can work out it shouldn't make a difference as only the top row of the bulkhead connector is powered isn't it, the rest is literally just a connector? for the two looms. Just want to make sure before I cut the wires.

The relay wants to be beween the bulkhead connector and the lights. If you're happy at the condition of the wire that you've used from the bulkhead connector to the fog lights, then snip that wire, use the bulkhead connector end as the low-current connection on the relay, and the other as the high-current output. So the switch and bulkhead connector are only carrying enough current to throw the relay.