Hey guys I'm still trying to troubleshoot the 4wd on this damn Blazer . Was gonna check the ground wire for tccm but I don't know where it's grounded to? Does someone know where the ground runs to? Better yet with pictures? And what should the ohm reading be if it does have a good ground? Thanks !!

 

I found a wiring diagram that someone posted on here, and it identifies the TCCM ground as terminal C10 which indicates it grounds at G202 on the left side of the instrument panel. When troubleshooting my bad TCCM I unplugged the connector and measured the resistance from there to the case of the alternator. There should be only an ohm or two if the wiring is good. If it is much more that single digits, I would try running another wire to a good ground spot and tying in to that. If you can find where it grounds, that is fine but if you can't look for another place you can tie in to the body for a ground. In my case the ground was good and that told me my TCCM was bad. I put a good used unit in (from ebay) and now it's working.