DRE Shift lights - tachometer feed assistance required

[zoli88]

I have purchased the dre shift lights for a 2012 academy car (sigma engine 125bhp) roadsport.

I am trying to locate the source of the tachometer feed that will work with the dre shift lights, ideally from the rear of the tachometer.

Does anyone know which wire is the correct feed and has anyone already fitted the unit to their sigma based Caterham?

Any help is appreciated, and if you have pictures that would be really helpful.

[Gingerbread Man]

I have one of these for my K series car. Caterham tacho and tee'd in behind the tacho as you wish to, I think the gauges are still the same.

The signal feed is white and black, the power is green and the negative/ earth is black.

So from my notes;

DRE blue to car black.
DRE Red to car green.
DRE green to car white with black tracer.

Edited by Gingerbread Man on Thursday 28th August 19:57

[KRL]

I did this on my Sigma a couple of years ago. As long as you are using the standard Caterham tacho do the following:
- Locate Green (ignition switched power)
- Cut green, and re crimp with the red shiftlight wire
- Locate WB wire (white with black tracer)
- Cut WB wire, and re-crimp with the green shiftlight wire - this is the tacho input
- Crimp on a ring connector to blue shiftlight wire (ground).
- Loosen nut in wiper mechanism directly above tacho hole in the dash and re-tighten with ring terminal in place.

[Gingerbread Man]

My DRE shift light never worked out for me. To start it appeared that the car wasn't sending a signal powerful enough to power both the shift light and the tacho. It would flash on randomly.

I then had help from a chap on here which got me so far. They both then ran together but the shift light would randomly light up as if it was getting a stray signal, a pulse at odd times. Made it very frustrating and it sat on my scuttle for years. I have no rebuilt the car (well basically) and it's off the car at the moment but the hole is still in the scuttle. Maybe I'll sit it back!

Earth issue maybe? Although it ran the tacho fine.

Just my ramblings. I have two of these lights. Same problem with both, so my car at fault.

[grenpayne]

Gingerbread man, my DRE shiftlights also did this when I first got them. Turns out there were two, not one black 'earth' leads behind the (standard CC) tacho, I'd inadvertently got the one that didn't work, but when I swapped to the other black lead the lights started to work as advertised. No idea if that is the same as your car, but it confused the hell out of me initially!

[Gingerbread Man]

grenpayne said:

Gingerbread man, my DRE shiftlights also did this when I first got them. Turns out there were two, not one black 'earth' leads behind the (standard CC) tacho, I'd inadvertently got the one that didn't work, but when I swapped to the other black lead the lights started to work as advertised. No idea if that is the same as your car, but it confused the hell out of me initially!

Both entering the tacho? VVC engine here.

[zoli88]

Thanks Gents, I am going to be attempting the installation this weekend.

If anyone has any pictures to aid the wire selection that would help, as I believe I have two Black and white wires next to eachother in the Tacho Harness. One on the end of the top row and one next to it. (one is white with Black stripe and the other is Black with White Stripe)

I will let you know how I get on

[Gingerbread Man]

Remove the tacho from the dash. Mines two knurled back nuts which can be undone by hand. Then unplug the wiring. These are the wires. Just trace them back a few inches.

[KRL]

zoli88 said:

Thanks Gents, I am going to be attempting the installation this weekend.

If anyone has any pictures to aid the wire selection that would help, as I believe I have two Black and white wires next to eachother in the Tacho Harness. One on the end of the top row and one next to it. (one is white with Black stripe and the other is Black with White Stripe)

I will let you know how I get on

Re-read my post

KRL said:

...
- Locate WB wire (white with black tracer)
- Cut WB wire, and re-crimp with the green shiftlight wire - this is the tacho input
...

[zoli88]

Gentlemen, thank you very much, I put them in last night and the wiring appears to be spot on. I have only run it up in test mode so far but it was recognising the revs so perfect....

Thanks for all your help