JDH3
Member
- Messages
- 12
- Location
- Payson Arizona
Correct Alternator for Alpha? BCM? Help please
Hi all. I’ve been chasing this gremlin for awhile now. Essentially the beast doesn’t recognize that it’s in park. All the shift lights work except park, it will light up sometimes when you turn the key to on but turns off immediately upon ignition. I have to finger the magic button under the boot to shift out of park.
The other nuances that are/seem to be involved with this are things like; you cannot leave it to idle without a spare fob as it will lock you out( as in it thinks it’s in drive), it does not unlock upon shifting into park( although sometimes it will if I rev the engine, more on that in a sec), headlights stay off until you shift out of park( 90% of the time), the rear passenger window does not go down(haven’t checked into that as the car seat is there and that’s ok with me)and probably a few things I’m not remembering or noticing I’m sure.
My rig is a 2008 Alpha. I’ve replaced the battery and terminals, went through all the fuses, replaced the shift interlock solenoid for funnsies, checked other solenoids for function. I did find where it looks like a aftermarket alarm was cut out with three wires hanging under the dash and a empty plug.
I thought for a long time it was the BCM until I found that revving the motor unlocks the doors sometimes and that has me thinking voltage regulator. The alternator checks fine on my meter and the autozone guys meter but does that check the voltage regulator? It doesn’t seem like it would to me but I’m ignorant of such things.
The Hummer is absolute beast other than that, runs and drives great although I need a new catalytic on it as it stinks running a long hill above 65mph. I am selling it as it is a extra vehicle now and it’s hard to explain that to some random on Craigslist. I bought it knowing the shift issue thinking I could fix it and the guy knocked a grand off(ended up paying 16 for it). It’s a beautiful thing but the wife won’t let me bust brush in it “it’s to nice for that” lol.
I have it scheduled for the dealership/saboteurs on Wednesday and would like to avoid the stoke/heart attack that they will elicit. I was reading through post and saw that you need the proper alternator for the H3 and couldn’t find/understand which one that would be. Any help or theories on what I’m looking at would be greatly appreciated. I did get the Chilton subscription out of pure frustration as a reference guide. Anywho, have a great day/night, JD
Hi all. I’ve been chasing this gremlin for awhile now. Essentially the beast doesn’t recognize that it’s in park. All the shift lights work except park, it will light up sometimes when you turn the key to on but turns off immediately upon ignition. I have to finger the magic button under the boot to shift out of park.
The other nuances that are/seem to be involved with this are things like; you cannot leave it to idle without a spare fob as it will lock you out( as in it thinks it’s in drive), it does not unlock upon shifting into park( although sometimes it will if I rev the engine, more on that in a sec), headlights stay off until you shift out of park( 90% of the time), the rear passenger window does not go down(haven’t checked into that as the car seat is there and that’s ok with me)and probably a few things I’m not remembering or noticing I’m sure.
My rig is a 2008 Alpha. I’ve replaced the battery and terminals, went through all the fuses, replaced the shift interlock solenoid for funnsies, checked other solenoids for function. I did find where it looks like a aftermarket alarm was cut out with three wires hanging under the dash and a empty plug.
I thought for a long time it was the BCM until I found that revving the motor unlocks the doors sometimes and that has me thinking voltage regulator. The alternator checks fine on my meter and the autozone guys meter but does that check the voltage regulator? It doesn’t seem like it would to me but I’m ignorant of such things.
The Hummer is absolute beast other than that, runs and drives great although I need a new catalytic on it as it stinks running a long hill above 65mph. I am selling it as it is a extra vehicle now and it’s hard to explain that to some random on Craigslist. I bought it knowing the shift issue thinking I could fix it and the guy knocked a grand off(ended up paying 16 for it). It’s a beautiful thing but the wife won’t let me bust brush in it “it’s to nice for that” lol.
I have it scheduled for the dealership/saboteurs on Wednesday and would like to avoid the stoke/heart attack that they will elicit. I was reading through post and saw that you need the proper alternator for the H3 and couldn’t find/understand which one that would be. Any help or theories on what I’m looking at would be greatly appreciated. I did get the Chilton subscription out of pure frustration as a reference guide. Anywho, have a great day/night, JD
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