electrical issues
#1
11-26-2006, 04:01 AM
electrical issues
1996 12-valve cummins 218k miles
I was out of town for two weeks and left my truck in the driveway. When I came home it started right up but after I turned it off it wouldn't start again....hmmmm....Batteries are new so I checked the grounds, wiggled wires etc. Started up and the voltmeter was flippin' out. Ran fine for two days. Died again, voltmeter read that it was way overcharging and the 'GEN' light was on, turned off truck and restarted and has ran fine for two more days untill this morning. I let it warm up and went to drive away with my headlights on and they started flashing on and of for maybe 2 seconds and then stayed lit. Dash lights did the same but not as severe.
Looked into it a little and found that there is not a voltage regulator on the alternator. Alternator seems to be good as it seems to be charging a little high on the dial. My question is what controls the charging system? A "power module" of some sort? Is there some sort of power seperator besides the fuse box? Electrical stuff like this is my weakness.
I was out of town for two weeks and left my truck in the driveway. When I came home it started right up but after I turned it off it wouldn't start again....hmmmm....Batteries are new so I checked the grounds, wiggled wires etc. Started up and the voltmeter was flippin' out. Ran fine for two days. Died again, voltmeter read that it was way overcharging and the 'GEN' light was on, turned off truck and restarted and has ran fine for two more days untill this morning. I let it warm up and went to drive away with my headlights on and they started flashing on and of for maybe 2 seconds and then stayed lit. Dash lights did the same but not as severe.
Looked into it a little and found that there is not a voltage regulator on the alternator. Alternator seems to be good as it seems to be charging a little high on the dial. My question is what controls the charging system? A "power module" of some sort? Is there some sort of power seperator besides the fuse box? Electrical stuff like this is my weakness.
#2
11-26-2006, 10:35 AM
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RE: electrical issues
Yes, there is a regulator for the alternator. This is built into the computer (PCM), however, and is not seperatly replaceable.
You might try the key trick (as outlined here) to get trouble codes. If you have a digital odometer, it will flash the PXXXX code, which you can find here. Otherwise, you will count flashes as was outlined in the first link I provided.
The PCM regulates output of the alternator based on two main things: line voltage and battery temperature (located underneath the battery there is a battery temperature sensor).
You might want to go to the 2nd Gen Ram section, they can probably help you better.
The PCM is not a cheap part, so, you want to make sure thats the problem before you get a differant one.
You might try the key trick (as outlined here) to get trouble codes. If you have a digital odometer, it will flash the PXXXX code, which you can find here. Otherwise, you will count flashes as was outlined in the first link I provided.
The PCM regulates output of the alternator based on two main things: line voltage and battery temperature (located underneath the battery there is a battery temperature sensor).
You might want to go to the 2nd Gen Ram section, they can probably help you better.
The PCM is not a cheap part, so, you want to make sure thats the problem before you get a differant one.