Wiring a Shift Light

From experience, if you want to wire a shift light into you 111s you might encounter the same problem that I did. Most shift lights can be wired into the ECU feed to the rev counter in the Stack unit. I initally tried this, but the shift light worked either intermittently or not at all.

Through a bit of reserch I found out that I would be better wiring the shift light feed to the signal to the coil pack, which is different on the VVC engine to a standared K.

Dave Andrews had this advice to give me:

"I would expect that the shift light would need a coil signal to calculate RPM, usually the low tension switch side of the coil is used for a signal so you might want to consider connecting to that either at the coil pack (tricky dicky) or at pin 25 of the MEMS.

The tacho signal from pin 12 is sometimes too 'square' for tachos/shift lights etc. The coil trigger signal (pin 25) is more of a round waveform and is sometimes better to use."

So I tried wiring it to the coil pack (low tension side) and bingo!, it worked!

You'll find that there are three wires on the low tension side, you should be able to use either of the outside wires. Just remember to set the Shift Light to 2 Cylinder mode, as it is now only receiving a signal for two of the cylinders!