Weber Shift Light

[Super_Rich_Bernie]

I bought a weber sequential shiftlight, which at just short of £60 seemed a bargain. This is comaptible with a Weber Alpha Ecu, or a coil driven feed. It has a row of lights which come on sequentially from 1000rpm below the set shift point.

 

Sadly I can't get it to work.....

 

I tapped it into the wires on the back of the existing tacho - using as the shiftlight instructions suggested, an ignition switched positive feed, and the input for the tacho (which comes from the ecu?). Final connection was to earth.

 

Being a cautious type with minimal knowledge of which wires go where behind the dash and having read that if I set the shiftlight to ecu feed it would harm it if it in fact received a coil feed, I tried it with the unit set to receive a coil feed which wouldn't harm it. I figured that this way I was Ok with 90% certainty that the tacho was ECU driven.

 

I then set it to ECU feed - and the lights come on, but randomly, and not at any set rev point. The ECU is not a weber one - it is an aftermarket Lumenition.

 

So if anyone has any ideas on the following I'd be interested to hear..

 

1. Is the tacho feed from one ECU going be the same as any other. I thought so since they all drive the same types of tacho? Or is a Weber alpha tacho feed some way unique?

 

2. If I give up on the ecu feed and try to tap it into the coil which lead do I need (1.6k series of 98 vintage, with a coil mounted down below the throttles/airfilter?

 

3. Anything else I'm missing?

 

Right now the shiftlight is back at the vendors, who are sending it back to weber to test. It may be faulty I guess.

 

yours in much confusion

 

Jonathan

[Luke Beaumont]

I had some problems but nothing like you've got. After finding the right wires, and hastily reading the manual, I opted for a 'try all combinations of jumpers' approach. Got there in the end. The other snag was that I had to triple the resistance on the adjustment pot to get it in the right range.

[Anthony]

The shift light feed on Weber Alpha 3D from recollection is a negative which needs to be connected to a positive if this helps