Can Anyone Explain How The Reverse Lights Are Wired In?

[Speed Freak]

as a lot of you already know, im getting towards the end of my s2000 project build.

the car before was running a zetec 1800 on tbs, and the westfield loom. just wondered how the reverse light actually works? is there a sensor in the gearbox which is in turn wired to the ecu?and from there to the light?

as Ive swapped to an s2000 engine and will be stripping back the entire s2000 loom to the neccessary bits, would I best off using the wiring from that to power the reverse light? or will it still somehow work with the new engine?

cheers

tim

[Norman Verona]

Each manufacturer may well wire them differently.

There is normally a switch on the gearbox that closes when reverse is selected. This provides the earth to the reverse lights which have a live wire(s) permanently connected,

I would suggest a feed from the rear sidelights to the reverse lights and then the earth from the reverse lights to the switch on the gearbox. This way the reverse lights only work when the side lights are on but it saves running a wire from the fuse box to the rear for the reverse lights.

[Dave Eastwood (Gadgetman) - Club Chairman]

In a Ford MT75 or Type 9 box its just a plunger type switch in the gearbox that's pressed in to close the circuit when you put the car in reverse. So on a WF, typically, there's 12 Volt to the switch, then a feed from the switch to the reverse lamp, then the other side of the lamp runs to a ground.

Don't know how Honda's done it with their 'box though.

[Speed Freak]

hummm, have to look into it. theyres a couple of plug in points to the gearbox from the main engine loom.. guessing it must be a part of that. would think speed and revs will be calculated through the gearing and obviously the ecu aswell.

[Captain Colonial]

I would say before you get too much further that a reversing light is not part of the MOT, so it depends how bothered you are by having one.

[Dave Eastwood (Gadgetman) - Club Chairman]

MOT maybe, but might be worth checking if the TüV test needs it.

[Captain Colonial]

Oh yeah. S**t. Nice catch.

[Dave Eastwood (Gadgetman) - Club Chairman]

[Speed Freak]

ive gotta have one for germany mate

[SootySport]

It would help if you told us which gearbox you have.

[Dave Eastwood (Gadgetman) - Club Chairman]

Sorry, don't really know enough about the S2000 to say, though I would have thought it pre-dated too much by way of multiple ecu/can-bus style technology. Forgive me, I can't remember how much of each loom you were planning to use, and just which instruments! The original Honda, may, as has been common for some time now, take a speedo reading from wheel speed sensors also used for ABS/traction/anti-skid type systems. What speedo do you plan to use? If you're keeping the VDO, then thats fine, it'll keep its original sensor and you can ignore the Honda's.

Rev counter feeds are typically supplied direct from the ecu. (The ecu usually uses either a crank position sensor or more rarely, a cam position sensor to determine what the actual rpm of the engine is.)

[Dave Eastwood (Gadgetman) - Club Chairman]

I thought it was the Honda S2000 'box, apologies if I've remembered wrongly.

[ACW]

Dunno if this helps - nicked off another forum

[Dave Eastwood (Gadgetman) - Club Chairman]

That sounds pretty similar to the Ford set up then.

[GreigM]

Would a switch on the dash which illuminated the rear light do? Thats how BECs with reverse lights work -saves messing around with wires from the engine.