Re: Salvaged MAC 11B ECU Working OK

["Douglas Hurst Quebbeman" <dougq@iglou.com>]

> The yellow wire goes to the fuel pump relay and the check engine
> light.  The Bentley representation of the fuel pump relay
> guts would appear to be incorrect and some other documentation
> I have indicates that pin 31 of the ECU goes to one contact
> in the RP relay, the other of which is grounded.
> 
> Bridging these two contacts would indeed be equivalent to
> grounding pin 31 at the ECU.  It should turn the check
> engine light on since the other side of the check engine
> light goes to +12V (switched and fused I think).

This did not yield the desired result of starting the output 
sequence.

 I gave up and went back to Plan A; I took apart an old 
100LS relay (actually turned out to be a solid-state device) and used 
the two brass connector pins I needed that would have been part of 
the fuse assembly. I soldered wires to the conector pins, and the 
other ends of the wires to a momentary spst pushbutton switch. That 
worked; the output tests bean. However, I almost immediately got a 
low-voltage indication, as I'd been inside the house for almost an 
hour while the ignition was turned on but the car not running. This 
nearly drained the battery. I started the engine; it's idling now, 
and I'm going to go for a short drive to check out an old C2-type 
5000 that may be abandoned.

The saga continues...
--
-Douglas Hurst Quebbeman      (dougq@iglou.com)
"The large print giveth, and the small print taketh away."  -Tom Waits