2nd Gen Non-Engine/Transmission Voltage regulator in computer ?

[rich224]

The light telling me to check my guages came on this a. m. Found voltmeter pegged to the negative side, made it home, removed alternator, brought it to a rebuilder, checked out to be nothing wrong with the alternator.

I made some calls and was told by a tarnsmission specialist that the voltage regulator was in the computer panel on the firewall. He called Auto Zone and they quoted him approx. $373. 00.



Is this for true ??? Any help from some guys with previous experience about this ?



Thanks, Richie



2001 Black Sport 3500 auto 4x4, plus "goodies"

 

[JLandry]

Richie,



*If* the voltage regulator circuit is at fault, then yes... it is internal to the PCM (Powertrain Control Module) located on the passenger side firewall.



A refurbished unit can be ordered on eBay from "Auto Computer Exchange" for $199 programmed with your truck's VIN and mileage, delivered to you. If they don't have a PCM listed for a truck equipped with a diesel engine, just use the "Ask Seller a Question" link on one of the PCM's they've listed for a gasoline equipped engine, and they'll fix you up. I bought a PCM from them and it works perfectly.



But I'm getting ahead of myself...



Before you think about replacing the PCM, have you checked for diagnostic trouble codes ? You can do this by turning the ignition key ON-OFF-ON-OFF-ON and watch the odometer window. Please report back what code (or the lack of) that you see and we'll try and supply the appropriate trouble shooting procedures.



Good luck,



John L.

 

[rich224]

Voltage regulator in computer ?

Hi John L.



It's raining in south Mississippi, been running out every time it quits to try to put the alternator back on. Got that and a new belt - - - - now - - -- I checked for codes, the PCU showed nothing, the ECU gave codes 0238,1475,0382, and 0380. I think the last two refer to the relays for the intake heater, I have been meaning to get those, but it never gets cold enough here to make a difference.



Thanks for the help,



Richie

 

[JLandry]

... the ECU gave codes 0238,1475

These first two codes seem to indicate a problem with your MAP sensor or the MAP sensor wiring harness. But I wouldn't mess with it until you straighten out your apparent charging problem.

0382, and 0380. I think the last two refer to the relays for the intake heater

Agreed.



Well assuming you have a charging problem with no related trouble code, then the Dodge Powertrain Diagnostic Manual suggests to check the following items:

1. Check generator belt tension.
   
2. Check that both batteries have less than 1 volt difference between them.
   
3. Connect voltmeter between generator B+ terminal and the battery (+) terminal. Start engine. The voltage reading should be 0. 4 or less. If higher, the circuit between the generator and battery has too much resistance and needs to be repaired.
   
4. Connect voltmeter between the generator case and the (-) terminal of the battery. The voltage reading should be 0. 1 or less. A higher reading indicates a poor ground of the generator and/or battery and must be repaired.
   
5. Measure voltage between fused B+ terminal at PCM connector and a ground. If this isn't the same as battery voltage, then excessive resistance is present in the circuit between the PCM and the battery and must be repaired.
   
6. If no problems are found with any of the above items, replace the PCM!
   

Hope that helps,



John L.

 

[WilsonF]

If you can't find anything else, this link gives some more good troubleshooting steps and-and how to wire in and external regulator that will control your alt. Save you allot of money and headaches. If I remember right it cost me about $15 for reg. at NAPA.

GEN light again! - Dodge Diesel - Diesel Truck Resource Forums
It worked on my 96 hope it will on your 01.
Floyd

 

[rich224]

Adding external voltage regulator

I tried the tip in "Gen. light again" , bought a 70's era external voltage regulator, cut the wires from the alternator, went to the new external voltage regulator, picked up a 12 V. "ignition on" source and what do you know - - - - the volt meter goes from 0ne side of the guage to the other.

Prior to this I had my alternator checked out and was told that it was good but the problem was the regulator, and "IT" was in the ECU. Trying not to buy a new computer, I tried the above "Fix".

Now the volt meter on the dash is showing 18 volts, I let it run for a little while, then when it didn't go down to around 14, I shut it down afraid that I would burn something up.

Where do I go from here ? Will I burn something up at 18 volts ?



Richie



2001 Black 3500 Sport 4x4, Edge Comp. , AFE, Bully Dog, FASS, Isspro guages

 

[rich224]

Just had a friend come by with a after market voltage guage and a multi meter. Both of them are reading just over 15 volts, but the guage in the dash is pegged at 18 volts. Should I put in an after market guage ? Is 15 volts too much ?



Richie

 

[AKAMAC]

Did you look at the IAT sensor/battery temp thermocouple and the grid heater circut? The alternator will not charge when the grid heaters are cycling.

With your codes for the heaters I would look at those for the problem. Check the IAT for resistance and the battery tc for mV.

 

[WilsonF]

Yes 18v is too much you will over charge the batterys and they will boil over. With the engine off put a multimeter on one of the two small connectors on the back of the Alt. then to the other. You may show continuity to ground on one of them but not both. With a ground your system is putting a demand on the alt. for a charge. If you do have a ground condition you will have to find out if it is in the alt. or some where else in the system.
Floyd