Wiring relay for halogen headlights

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Jamp

Wiring relay for halogen headlights

#1 Post by Jamp »

Hi All

I've got the halogen kit for my 1500 from Rimmer Bros but they didn't include the instructions and said they would forward them later but haven't done so. I can't be bothered to chase them as I want to get them installed this week, so am after some advice re the relay wiring. They've included a Lucas relay with 5 terminals, 4 of which are labeled C1 C2 W1 W2, the fifth looks like it may be a second C1 but is unlabeled.

I was expecting 6 terminals - effectively 30 for power (fused - not included in the kit :() and 86 for earth, then 85(i) and 87(i) for trigger and supply for main beam, and 85(ii) and 87(ii) for trigger and supply for high beams. I don't see how a 5 terminal relay can achieve this - it is a big heavy relay though and is all they've included.

Anyone have any advice or should I just bin the Lucas relay and use two normal Bosch-type relays, one for main and one for high beams. I'd prefer to use the Lucas as it'd save me a long trip to Maplin.

Cheers,

Ben
1300dolly

#2 Post by 1300dolly »

it can be done with the 5 teminal but i couldn't tell you how from memory. if you want to be lazy pop into hellfrauds and they do a pre wired relay kit complete with idiot guide.
Lewis

#3 Post by Lewis »

They do? Fantastic?

My main beam contacts are shot, burnt out from the halogens. Flash still works mind....then again, I guess the contacts could be OK but something mechanical could be amiss. In fact, it might even have relays on it. Not even looked!

Yet to investigate :)
Nick C

#4 Post by Nick C »

I've heard that the contacts on the column switch can fail if the whole system is relayed, as they corrode without the full current to burn the corrosion off. The solution I was given was to relay just the inner main beams, leaving the outer beams running through the switch, so there is enough current to keep the contacts clean, but not enough to burn them out.
Jamp

#5 Post by Jamp »

Thanks for the replies.

Nick, relaying the inner pair sounds a good solution. Is the switch the only weak point likely to suffer from the higher current drawn by the halogens? If so I will just do as you suggest and relay the inner pair. Would you suggest doing this under the dash, triggering from the switch, or just forget the inner pair's loom and trigger from the outter pair's high beams and power direct from the battery?
Jon Tilson
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Ive seen...

#6 Post by Jon Tilson »

loads of burnt out switches in my time so I would reckon a realy is essential for the halogen inners.
Ive not heard of Nicks theory beofre but I suppose its plausible. I do find as a general rule that its the low current electrcis that give grief, except the horn.

I'd fuse the inners, feed direct from the fuse box to the power side of the relay and on to the lights. Then take the realy control switch feed from the existing main beam circuit. If that doesnt make sense ask again...

Jonners
Note from Admin: sadly Jon passed away in February 2018 but his humour and wealth of knowledge will be fondly remembered by all. RIP Jonners.
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