2005 PLSOR cuts after starting

[Harkonnen]

if so why not add a direct B+ supply to the suspect part as a test or monitor it with a test lamp or vom to see whatahappens when you release the starter cct.

That's roughly my next step once oscilloscope arrives. I bet I'll see a voltage dip on R/Pu when starter disengages and work from there.

 

[saltchuckmatt]

One plug, one jumper wire....so easy.

 

[Harkonnen]

Nope. Not on the powerpack, not on the diagram. Y/R starts at ignition switch, runs to shift interlock and then aft to solenoid. Nothing else is connected to it as far as I can see.

Oops, I guess there IS a weird Y/R branch to powerpack. I stand corrected.
So if it supplies juice to the pack while cranking, and then coils take over, except that they don't, and coils are nominal, what is my problem, then?

Safe enough to disconnect Y/R at the pack and see if it runs with straight 12v to the pin, what do y'all think? I don't trust those semiconductors.

Progress. I give Y/R pin at powerpack 12V and engine runs until I disconnect it. Must be a problem with handing over to coils.

 

[Crosbyman]

is this a new to you engine... anybody worked on it YR is typical START .

any chance "a purple" should go to the power pack ? ...sorrry I don't have a diagram but it seems that woud solve the problem