Pcm ground

[Darrenmb]

Still working on my swap into the jag, thought I was ready to try to start it, turned key on, no fuel pump prime and no check engine light, I have 12 volts everywhere I am supposed to, however what about grounds? Where do the they come from? Just a quick glance on shoebox site. Shows 2 grounds on red pcm connector alone, where is the other end of those???? What am I missing????

[Darrenmb]

I see the ground wires by the coil.. is that all of them? Just two whites tied together and a black???

[Injuneer]

Remind us.... what year is the PCM and harness?

[Darrenmb]

Sorry, everything is from a 94 pontiac formula

[blkchevyz]

its down by the motor mount and starter.

[Injuneer]

See Shoebox’s photo of 94/95 harness. The black PCM ground has an eyelet to attach to the block as described above. It is bundled with the wire for the pass side O2 sensor, knock sensor, and purple starter wire.

http://shbox.com/1/harness.htm

http://shbox.com/1/harness3.jpg

[Darrenmb]

My post dissapeared... oh well, thank you guys, I know that wire is hooked up as it's one if last ones i did, however I put it on an Oil pan bolt as I had run out of spare bolts, wonder if thats my issue..

[Darrenmb]

Just an update, ground was fine, was the 12 switched ( pink wire ) was bad, had 12 volts, about an inch away from the connector and 2.7 volts at the connector, fixed that, now I get my check engine light and my fuel pump prime.. still wont start though but best I can tell that is fuel pressure related..

[Injuneer]

The PCM has 4 ground terminals. Two of them (A2, C32) have black/white wires that connect to the same large splice, where it joins grounds from:
- oil level sensor
- MAF sensor
- a single wire from another splice that includes:
— DLC connector
— theft deterrent module
— trans position switch (A4)
— fuel pump relay
— instrument cluster
— traction control switch

The above connects to ground G103, a stud on the block above the starter.

The other two terminals (A18, D1) have tan/white wires that connect to ground G102, the stud on the block below the driver side head that holds the ICM/coil bracket. That stud also has a black wire from a splice connecting grounds from:
- A/C compressor clutch
- ignition coil module
- O2 sensor, bank 1
- O2 sensor, bank 2.

There should also be a braided ground strap that connects to the driver side frame rail.

What's the code for the SES light?

[Darrenmb]

Ok, having issues with editing above post for spelling and autocorrect issues keeps telling me invalid page.. but whack is supposed to say eehack and other gobblygook word is check for spark... sorry, typing on phone