[Gmecm] Shift light

[bcroe at juno.com]

I believe if you actually connect the light, it will then go 
to battery voltage when off.  Bruce Roe

24 Jun 2006  "Robin Handley" <Robin at FuryWorld.fsnet.co.uk> writes:
> Anybody played with the shift light (pin A12) in a '727 or its 
> equivalent in a '749?
> 
> Going by the circuit diagram for a '727, ignition volts are 
> supplied to the non-ECM side of the shift light. My limited 
> electrical knowledge tells me that the ECM ground this pin 
> when it wants the light to come on. So, when it wants the 
> light to be off, the pin should be at battery voltage. Is this
> right? Same deal for the injector pins?
> 
> Could be my minimalist installation causing bypasses in 
> logic (although can't see why), but I see no voltage on the 
> shift light pin, whether the RPM is below the light 
> on threshold or not. Am I missing something?
> 
> Robin