First time post here guys, i think this is where this belongs..
2007 GMC Yukon
So, i was driving down the road when, suddenly, "charging system failure" or "service charging system" displays on the dic. Voltmeter gauge showed voltage down to about 10-11 volts, battery light illuminated. So I'm thinking, great my alternator just went.
I continue driving to my stop and let it run for fear i wont be able to restart. I get home and shut her down in the driveway and try to restart to see what happens. Of course, there's a weak crank and no start. I've been driving on just battery for about 12-15 miles, battery is pretty dead. Try again, no crank. This was the last time she cranked (2 weeks ago).
Ok, I attempt a jump start with another car and nothing, no crank. The gauges are lit up, but nothing happens when i turn the key. I let it "charge" from the other car for a good 45 min., until voltage was reading 14v (up from 11.86v). Hop inside and try again, nothing, no crank, no click, dash lights don't even go out.
It's at this point i realise that the interior dome lights didn't come on when i opened the door. Also, service stabilitrak, service traction control were displayed on dic. I notice also that the rear power windows aren't working, from either master driver switch or their respective switches. The lock/unlock switch doesn't work, not on the doors or the key fob. The lift gate doesn't work. My blinkers do not work, my hazards don't work, the little shift indicator doesn't work. I can see PRND12 but there is no underline beneath P or any spot on the column.
The radio works, i can manually turn on the headlights. The dash lights up, i hear door chimes. The electric seat works, well driver's at least haven't tried passengers. Front power windows work from both switches. I did notice, however, when i squeezed the driver side loom running from body to door i would hear a click at the switches and the front windows would stop working. I cut open the water proector to find the black wire completely severed. I soldered it back and the front windows again were working. I dont think thats related. Didnt see any other damged wires. And that's about it..
All fuses appear to be good. However, no power is being sent to liftgate, checked at fuse block under hood. In the fuse panel inside, no power is even being sent to LCK1, LCK2, UNLCK1, UNLCK2.
From what I've read, people with similar situations claim it was a bad BCM. I took mine out, took the board out and, visually, nothing appears burned or blown, no bad solder joints. Maybe something internally that can't be seen idk.
Does the power or signal for these systems come from the BCM?
Could a failed alternator take down the BCM?
What do you guys think?
FYI.. Battery tested as good, alternator bad, bad all around they said. In fact, i threw the yukon battery in my trailblazer, which has been sitting for a year, and she started right up. Been driving that in the meantime.
2007 GMC Yukon
So, i was driving down the road when, suddenly, "charging system failure" or "service charging system" displays on the dic. Voltmeter gauge showed voltage down to about 10-11 volts, battery light illuminated. So I'm thinking, great my alternator just went.
I continue driving to my stop and let it run for fear i wont be able to restart. I get home and shut her down in the driveway and try to restart to see what happens. Of course, there's a weak crank and no start. I've been driving on just battery for about 12-15 miles, battery is pretty dead. Try again, no crank. This was the last time she cranked (2 weeks ago).
Ok, I attempt a jump start with another car and nothing, no crank. The gauges are lit up, but nothing happens when i turn the key. I let it "charge" from the other car for a good 45 min., until voltage was reading 14v (up from 11.86v). Hop inside and try again, nothing, no crank, no click, dash lights don't even go out.
It's at this point i realise that the interior dome lights didn't come on when i opened the door. Also, service stabilitrak, service traction control were displayed on dic. I notice also that the rear power windows aren't working, from either master driver switch or their respective switches. The lock/unlock switch doesn't work, not on the doors or the key fob. The lift gate doesn't work. My blinkers do not work, my hazards don't work, the little shift indicator doesn't work. I can see PRND12 but there is no underline beneath P or any spot on the column.
The radio works, i can manually turn on the headlights. The dash lights up, i hear door chimes. The electric seat works, well driver's at least haven't tried passengers. Front power windows work from both switches. I did notice, however, when i squeezed the driver side loom running from body to door i would hear a click at the switches and the front windows would stop working. I cut open the water proector to find the black wire completely severed. I soldered it back and the front windows again were working. I dont think thats related. Didnt see any other damged wires. And that's about it..
All fuses appear to be good. However, no power is being sent to liftgate, checked at fuse block under hood. In the fuse panel inside, no power is even being sent to LCK1, LCK2, UNLCK1, UNLCK2.
From what I've read, people with similar situations claim it was a bad BCM. I took mine out, took the board out and, visually, nothing appears burned or blown, no bad solder joints. Maybe something internally that can't be seen idk.
Does the power or signal for these systems come from the BCM?
Could a failed alternator take down the BCM?
What do you guys think?
FYI.. Battery tested as good, alternator bad, bad all around they said. In fact, i threw the yukon battery in my trailblazer, which has been sitting for a year, and she started right up. Been driving that in the meantime.
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