P1637 and P1638
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From: http://www.mphparts.com 800-364-1975
P1637 and P1638
I am getting both of these codes and my alternator is not charging, at all. I have checked voltage on the two red wires against chassis ground and against the grey wire on the alternator harness, and one shows 12v, the other 10.7v.
The 10.7v reading is surprising to me -- I would expect it to either be 12v or 5v. In fact the service manual says when checking for issues related to P1637 to check for 5v on the lead. I am not sure if they mean to check for "at least" 5v.
Anybody know for sure?
The 10.7v reading is surprising to me -- I would expect it to either be 12v or 5v. In fact the service manual says when checking for issues related to P1637 to check for 5v on the lead. I am not sure if they mean to check for "at least" 5v.
Anybody know for sure?
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From: http://www.mphparts.com 800-364-1975
Ttt... anyone?
Does the alternator need its chassis grounded to the block? I recently had my alternator bracket powder coated so it's likely it's not getting a good ground back to the bracket (and thus the block). I did a lot of things at once though (new motor, twin turbos, etc.) so I can't tell if the alternator stopped working right after the powder coat or if it was something else.
Does the alternator need its chassis grounded to the block? I recently had my alternator bracket powder coated so it's likely it's not getting a good ground back to the bracket (and thus the block). I did a lot of things at once though (new motor, twin turbos, etc.) so I can't tell if the alternator stopped working right after the powder coat or if it was something else.
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From: Ohio
Originally Posted by diynoob
Ttt... anyone?
Does the alternator need its chassis grounded to the block? I recently had my alternator bracket powder coated so it's likely it's not getting a good ground back to the bracket (and thus the block). I did a lot of things at once though (new motor, twin turbos, etc.) so I can't tell if the alternator stopped working right after the powder coat or if it was something else.
Does the alternator need its chassis grounded to the block? I recently had my alternator bracket powder coated so it's likely it's not getting a good ground back to the bracket (and thus the block). I did a lot of things at once though (new motor, twin turbos, etc.) so I can't tell if the alternator stopped working right after the powder coat or if it was something else.
The alt DOES ground through its housing! Hope that is the problem. If you not sure it is grounding try running a seperate wire to the frame. Also many shope will check your alt for free.
Last edited by GRAY BEARD; Oct 25, 2006 at 04:09 PM.
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From: http://www.mphparts.com 800-364-1975
Yeah I asked another guy around here that works on a lot of these cars if it needed to ground through the bracket and he said it did. So, noob mistake on my part (but at least I knew enough to question whether it needed to be grounded through the bracket!)
I am going to run a 4 gauge lead off the alternator to the frame since I don't feel like scuffing up my beautiful powder coat
I am going to run a 4 gauge lead off the alternator to the frame since I don't feel like scuffing up my beautiful powder coat
