Technical Replacement headlight switch.

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Technical Replacement headlight switch.

vale of uscon

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Nov 20, 2009
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All,

I’ve a problem with my light switch of a 1500cc 1985 model.
Does anyone have a replacement.

Thanks in advance
Simon
 
Simon, sorry I don't have a switch but I do suggest fitting relays to your headlights (I fitted 4, one for each filament - RH dip, LH dip, RH main and LH main each relay fed from its own fuse). This takes almost all the current away from that switch and improves voltage on the bulbs from about 9volts to 13volts in my car, headlights with std H4 bulbs are as good as any halogen bulbed car now.
 
Scotty,

Sounds great, unfortunately I wouldn’t have a clue were to start when it comes to wiring.
I’ll see if I can find a I tube link or two for ideas.
Thanks
Simon
 
Simon, sorry I don't have a switch but I do suggest fitting relays to your headlights (I fitted 4, one for each filament - RH dip, LH dip, RH main and LH main each relay fed from its own fuse). This takes almost all the current away from that switch and improves voltage on the bulbs from about 9volts to 13volts in my car, headlights with std H4 bulbs are as good as any halogen bulbed car now.

Hello Scotty

could you explain in details how you did this please?
ie where did you get the feeds from, where did you put the relays, did you use the old 6 terminal switch or the Panda 4 terminal.

cheers

RDS
 
Hi RDS.
What I did was basically quite simple, for the headlights I installed 2 relays inside each headlamp pod hatch - where all the wires for the headlamps are. I bought a couple of new H4 bulb connectors and crimped 1/4" female spades onto the wires for that. So one wire - the bulb common goes to the dreaded earth turret. The other two bulb filament wires go to the relays - the N.O. contacts (I used the miniature style relays) I used a couple of male spade terminals to feed the relays coil from the connector that used to go to the back of the bulb. So the 12v that used to feed the bulb directly now only feeds the relay coil. The other coil terminals go to earth. The relays common is fed via a pair of nice thick 2mm2 or even 3mm2 wires that go via the grommet back to a new fuse box I mounted next to the battery. I used an 8way fusebox so 4 for the headlamps and 4 for other "Brown wire" type of mods I did. All +12v fed via thick wires from an 80amp midi fuse coming directly off the battery +12v.
So, back to the headlamps relays, each relay has its own fused high quality power feed so if any bulb blows and takes out its fuse then the other 3 bulb filaments still work and you can still see to drive.
If you think about it, the relays are energised as the bulbs used to be and in turn the relays contacts just switch their new +12v directly to the bulbs.
You need to repeat the same on the other side of the car of course. I think this gives the very best possible 12v to the bulbs, in my case I measured 9.6v at the bulbs before and after my relays and wiring mods +13.5volts. The ordinary H4 halogen bulbs are now really bright and usable now. I know this is all a bit of a faf but it is the proper way (I used to work in Jaguar Electrical).
Headlamp switch - its still the original factory one, I just took the load off it and route the heavy current directly from the battery.
I also did my own design 70amp relay circuit fed from the ignition switch to supply the fusebox big red wire. Glutton for punishment, I went on to stick a couple of relays near each A pillar to help the windows go up and down much better (also fed from these extra fuses) and have still to sort out my wiper relays (but don't drive it in the rain!!).

I did spend evenings reading about others electrical issues and struggled to understand wiring descriptions of these mods (so you are excused if mine make little sense) and it all became clear to me when I drew out the circuit diagrams for them in my own way.
Welcome to contact me again if you have any further questions RDS.
 
Hi RDS.
What I did was basically quite simple, for the headlights I installed 2 relays inside each headlamp pod hatch - where all the wires for the headlamps are. I bought a couple of new H4 bulb connectors and crimped 1/4" female spades onto the wires for that. So one wire - the bulb common goes to the dreaded earth turret. The other two bulb filament wires go to the relays - the N.O. contacts (I used the miniature style relays) I used a couple of male spade terminals to feed the relays coil from the connector that used to go to the back of the bulb. So the 12v that used to feed the bulb directly now only feeds the relay coil. The other coil terminals go to earth. The relays common is fed via a pair of nice thick 2mm2 or even 3mm2 wires that go via the grommet back to a new fuse box I mounted next to the battery. I used an 8way fusebox so 4 for the headlamps and 4 for other "Brown wire" type of mods I did. All +12v fed via thick wires from an 80amp midi fuse coming directly off the battery +12v.
So, back to the headlamps relays, each relay has its own fused high quality power feed so if any bulb blows and takes out its fuse then the other 3 bulb filaments still work and you can still see to drive.
If you think about it, the relays are energised as the bulbs used to be and in turn the relays contacts just switch their new +12v directly to the bulbs.
You need to repeat the same on the other side of the car of course. I think this gives the very best possible 12v to the bulbs, in my case I measured 9.6v at the bulbs before and after my relays and wiring mods +13.5volts. The ordinary H4 halogen bulbs are now really bright and usable now. I know this is all a bit of a faf but it is the proper way (I used to work in Jaguar Electrical).
Headlamp switch - its still the original factory one, I just took the load off it and route the heavy current directly from the battery.
I also did my own design 70amp relay circuit fed from the ignition switch to supply the fusebox big red wire. Glutton for punishment, I went on to stick a couple of relays near each A pillar to help the windows go up and down much better (also fed from these extra fuses) and have still to sort out my wiper relays (but don't drive it in the rain!!).

I did spend evenings reading about others electrical issues and struggled to understand wiring descriptions of these mods (so you are excused if mine make little sense) and it all became clear to me when I drew out the circuit diagrams for them in my own way.
Welcome to contact me again if you have any further questions RDS.

I don’t have the nerve for messing about with the wiring but that all makes sense and all sounds very clear.
 
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