New alternator and battery, but no charge to the battery? ECM maybe? Saturn Vue.

mtgsource

Well, here's what happened. I was driving the truck (2006 Saturn Vue 2WD 3.5L) in town and all of the sudden the AC stopped blowing cold air and just blew normal warm outside air. Then the Battery dash light came on, the the ABS dash light came on, then the Seatbelt light came on and we both were wearing them. I lost power steering and it became very "jerky"as if it were only being assisted a little bit here and there. I swung the truck into Advance Auto Parts (how lucky). The dash lights were kind of coming on and then go out and come back on again. The truck then stalled in park gear. I tried to restart, but the battery was dead. I had Advance check the battery and they said it was good, but the alternator was bad coming in at a low voltage of 6.5. An auto repair shop was across the street and they helped me to get it there. They checked the battery and the alternator and came up with the same conclusion except that the battery was bad and it also had a battery that was too small in CCA for the truck. Supposedly the battery should have been around 650 CCA and there was only a 550 CCA installed. Anyways, I got a new alternator from Advance and the repair shop put in a new battery to go with it, but when testing they found that there is no charge going to the battery from the alternator? What? They just got done checking all of the ground wiring from the alternator to the starter and from the starter to the battery and it was clean. They said they used a Power Probe machine tester to check for electrical continuity and everything came back good. They did say that it most likely is in the ECM. There is also a BCM isn't there? What do the both control and what is their difference? Do i need to get an ECM flashed and reprogrammed if I find one? Which ECMs can I use and if so, can they just pop in into the truck and have it work?

aimeewoods

2004 Saturn Vue manual transmission. Purchased 2005 with 30K miles. Had to replace slave cylinder and ignition switch at 40K miles and leaking gas tank at around 60K miles. I was so frustrated that I was about to give up on Saturns, but then we had a span of 6 good years with few problems. Our Vue is now at 150K miles and I just replaced the right wheel bearing, serpentine belt and battery last month. The odometer light burned out. Then suddenly, last night, my battery light intermittently comes on. Took her to Autozone and altenator/battery both checked out fine. We were 60 miles away from home so we decided to cut our trip short and turn around. We made it 45 miles and the entire dashboard lit up (ABS/traction/service light). The battery died and we had to have her towed 15 miles home. Now our Vue obviously won't start because the battery is completely drained. I'd prefer not to spend another $1,000 figuring out what's wrong after just dumping $700 on the other repairs. I've come down to either the BCM/ECM... a bad ground wire to battery... or possibly a bad altenator (last resort). Just extra info: There's a burning scent (like burnt cheerios) after an extended time of driving. Please let me know what you found out with your Vue. Thanks!