Rewiring the main lights with relays

[JonB]

Hi

A report and some pictures of my fitting of relays to the S130/5's front lights. First off, the wiring diagram.

Schematic

• The battery terminal is the main connector on the starter relay.
• The Chassis connection is the offside chassis bolt in the engine bay by the radiator overflow bottle.
• Relays are 30A rated, with inbuilt fuses. 15A or 20A blade fuses should suffice. These units cost less than ?3 each from a well known auction site.
• I used the existing power feeds from the Elan's loom at the nearside pod. The offside pod loom is disconnected.
• A combination of bullet and spade connectors are used as appropriate. The conversion is completely reversible.
• Existing ground connections on the nearside and offside looms are wired to the new ground just in case.

New +12v connection at the starter solenoid. The wire is routed past the radiator bottle to pick up the new chassis connection.

New ground connector. This is a locking washer with the bare wire wrapped around it twice.

[JonB]

The relays are near the nearside pod.

Relays and loom

From the loom connected to the relays, a ground and two red wires (dip and main) pass across the front of the car to the offside pod. The new ground is connected to the Elan's loom ground connector on both sides of the car.

Offside pod wiring

The relays are just lying under the nearside pod at the moment. I will fix them in due course, but all this wiring needs to be protected from water ingress, given that it is sitting in the nose cone. I was thinking of enclosing the relays in a small waterproof box and screwing it into the bulkhead just below the nearside pod buffer. The wires will need tidying up too, and clipping down.

A quick test in the dark proved the approach. My lights are a good deal brighter and the thermal cutout did not trip and plunge me into darkness.

[lotusS2guy]

A simpler, albeit more expensive, solution is a kit from Painless Performance Products #30815.

http://www.painlessperformance.com/webcat/30815

It plugs into the original headlight sockets, so there is no rewiring (or thinking) necessary and is instantly reversible. I have this kit on my Elan and the wife's 280ZX. Very satisfied.

[JonB]

I bet it costs more, though. Looks like a nice product.

Mine cost about ?15 all in. The biggest expense was the wire, funnily enough.

[nmauduit]

I bet it costs more, though. Looks like a nice product.

Mine cost about ?15 all in. The biggest expense was the wire, funnily enough.

in the vicinity of 200 ... you won your bet !

[lotusS2guy]

Time is money.

[JonB]

Blimey!

It was very satisfying when mine worked first time. Not a complex circuit, of course.

[JonB]

I mounted the relays with self tappers just behind the vacuum actuator. Fitted 10A fuses and tidied the wires up. Working well, I'm pleased. Fog lights nice and bright as well.

If you have an S130 and you haven't got relays, put them in. Makes a world of difference and it's very cheap to do.

Now on to the next problem...

[William2]

I used one of these relays in my horn circuit. What a brilliant idea to incorporate the fuse in the relay.

[gus]

Are there not relays to begin with?

[JonB]

Are there not relays to begin with?

Lotus decided to remove them on the S130 models, probably due to cost cutting. Bad decision, but easily rectified.

[JonB]

I used one of these relays in my horn circuit. What a brilliant idea to incorporate the fuse in the relay.

According to the S130 wiring diagram, the horn does have a relay. In fact I think it is the only relay on there, other than the starter solenoid (technically a high current relay). Not even the window winders have 'em..

[Bigbaldybloke]

I?ve fitted my relays and fuses as shown on the photos, they are out of the way and not in direct line of water etc coming in the intake. I?ve got a fuse for each headlight.

[JonB]

That is really nice work. Good idea to label them, and the looms look good in that mesh wrap.

On my car, there is a plate between the radiator and the body (to help force more air through the rad) so I cannot do as you have done - also the horn relay (or is it the fan?) and remote vacuum valve is there. Oh, and the VIN plate, too. I see you have a modern shrouded fan on your rad so the removal of the side plates doesn't affect your car. Mine has the original fan which is a bit rusty and the blades have crumbling yellow paint.

I think I could tidy my relay installation up greatly, but it does require time and thought. My engine bay is quite a bit less clean than yours, too. Fortunately, my installation is totally reversible so I can go back later and improve things.

[Bigbaldybloke]

I?ve still got to find somewhere for the horn relay and the headlight vacuum solenoid, plus mine is clean as it?s being rebuilt from a body off respray and replacement chassis and hasn?t run in years so no chance to get mucky!