Go Back  DodgeForum.com > Dodge Trucks > Dodge Ram > 2nd Gen Ram Tech
Reload this Page >

Bypassing the PCM for an external voltage regulator?

2nd Gen Ram Tech 1994-2001 Rams: This section is for TECHNICAL discussions only, that involve the 1994 through 2001 Rams. For any non-tech discussions, please direct your attention to the "General discussion/NON-tech" sub sections.

Bypassing the PCM for an external voltage regulator?

  #1  
Old 01-01-2017, 10:18 PM
AtomicDog
AtomicDog is offline
Record Breaker
Thread Starter
Join Date: Sep 2012
Location: Central VA
Posts: 1,915
Likes: 0
Received 0 Likes on 0 Posts
Question Bypassing the PCM for an external voltage regulator?

Does anyone know where I can find clear documentation on how to install an external regulator and bypass the PCM so that the alternator will properly produce voltage to power the truck and keep the battery charged? I ran into a guy today that has a 2001 Ram 1500 2wd truck and his PCM's voltage regulator has failed. He wants to perform a budget repair with an external regulator to keep the truck going.
 
  #2  
Old 01-01-2017, 10:38 PM
94Beater's Avatar
94Beater
94Beater is offline
Professional
Join Date: Aug 2007
Location: Phoenix, Arizona
Posts: 244
Likes: 0
Received 0 Likes on 0 Posts
Default

The alternator already produced regulated 12Vdc. I'm not sure what is it that you are trying to do. PCM voltage regulator will make 5Vdc and maybe other DC voltage, but this is obtain by using onboard DC to DC converter. Its converted from 12Vdc. Not something easily replaceable or upgradable.
If anything you can use additional voltage regulators for the 12Vdc side to make your power system tougher.
Use something like this https://alternatorparts.com/quicktif...rectifier.html
 
  #3  
Old 01-01-2017, 11:36 PM
frankie_b_jr's Avatar
frankie_b_jr
frankie_b_jr is offline
Captain
Join Date: Sep 2013
Location: Nevada
Posts: 538
Received 0 Likes on 0 Posts
Default

Here is a link to a decent write-up... http://www.backyardmechanic.org/how-...jeep-chrysler/.

94 beater, the pcm makes or breaks the ground (iirc) to make the alternator maintain voltage. Unfortunately they do quit working, leaving the option like above or replacing the pcm.
 
  #4  
Old 01-02-2017, 12:35 AM
dbbd1's Avatar
dbbd1
dbbd1 is offline
Record Breaker
Join Date: Sep 2015
Location: Oregon
Posts: 1,552
Likes: 0
Received 0 Likes on 0 Posts
  #5  
Old 01-02-2017, 02:26 AM
AtomicDog
AtomicDog is offline
Record Breaker
Thread Starter
Join Date: Sep 2012
Location: Central VA
Posts: 1,915
Likes: 0
Received 0 Likes on 0 Posts
Default

frankie_b_jr and dbb1 are in the ballpark of what I'm looking for. The PCM is not properly regulating voltage on this person's 2001 Dodge Ram 2wd truck (which seems to be a very common issue on 2nd gen truck PCMs) and I was looking for a very concise write-up on how to bypass the PCM and wire-in an external voltage regulator to handle the voltage regulation duties.

Another option may be how can the PCM be do-it-yourself repaired to fix the internal regulator?
 
  #6  
Old 01-02-2017, 09:43 AM
HeyYou's Avatar
HeyYou
HeyYou is online now
Super Moderator
Join Date: Apr 2010
Location: Clayton MI
Posts: 57,634
Likes: 0
Received 34 Likes on 34 Posts
Default

There is no DIY repair on internal components of the PCM. If it fails, you replace it. The average DIYer doesn't have the equipment to deal with them. Even 99.99% of shops don't. Specialized equipment is required, and isn't exactly something you would find in the typical garage. (private, or commercial....)
 
  #7  
Old 01-02-2017, 10:29 AM
gertie240
gertie240 is offline
Captain
Join Date: Jun 2010
Location: San Antonio,Texas
Posts: 556
Received 0 Likes on 0 Posts
Default

he could get this kit, https://alternatorparts.com/external...nator-kit.html but the write is good, read through it and in the end it says to add a 194 bulb to trick the pcm
 
  #8  
Old 01-02-2017, 11:07 AM
AtomicDog
AtomicDog is offline
Record Breaker
Thread Starter
Join Date: Sep 2012
Location: Central VA
Posts: 1,915
Likes: 0
Received 0 Likes on 0 Posts
Default

What about this for taking a shot at repairing the PCM in do-it-yourself mode?

 
  #9  
Old 01-02-2017, 11:15 AM
dbbd1's Avatar
dbbd1
dbbd1 is offline
Record Breaker
Join Date: Sep 2015
Location: Oregon
Posts: 1,552
Likes: 0
Received 0 Likes on 0 Posts
Default

Nice video but my PCM ('99) is pretty well sealed with epoxy and not field repairable by the average joe/Jane.
 
  #10  
Old 01-02-2017, 11:21 AM
AtomicDog
AtomicDog is offline
Record Breaker
Thread Starter
Join Date: Sep 2012
Location: Central VA
Posts: 1,915
Likes: 0
Received 0 Likes on 0 Posts
Default

dbbd1, is your PCM sealed externally or are you referring to the gell inside of it? A photo would help, if available.
 

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: