Voltage regulator location?

Tiny
93DODGEGIRL
  • MEMBER
  • 1993 DODGE RAM
  • V8
  • 4WD
  • MANUAL
  • 130,000 MILES
Battery won't charge. Just replaced the alternator. Is there a voltage regulator somewhere?
Wednesday, June 3rd, 2009 AT 10:56 AM

9 Replies

Tiny
BLUELIGHTNIN6
  • MECHANIC
  • 16,542 POSTS
Voltage regulator is internal to the PCM for some Vans, on others the voltage regulator is located on the firewall small metal box with two or three wires here is a diagram below. Check out the diagrams (Below) Please let us know if you need anything else to get the problem fixed.
Was this
answer
helpful?
Yes
No
-1
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
ADARAN
  • MEMBER
  • 1 POST
  • 1991 DODGE RAM
Where is the voltage regulator?
Was this
answer
helpful?
Yes
No
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,128 POSTS
It is in one of three places, on the rear of the alternator, on the firewall, or internal in the PCM. I believe yours is in on the firewall. Here is a picture of one on the firewall:


https://www.2carpros.com/forum/automotive_pictures/249084_5_102.jpg



Let me know if this helps.
Was this
answer
helpful?
Yes
No
+2
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
DANSGIRL1967
  • MEMBER
  • 1 POST
  • 1990 DODGE RAM
We can not find the external voltage regulator on this dodge truck can you help us please
Was this
answer
helpful?
Yes
No
-1
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,727 POSTS
The voltage regulator is on the fire wall near the distributor. Here is a wiring diagram so you can tell the wire color to confirm the right part. (below)

Sometimes the computer will take over the job in some models.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

It's very rare for the regulators in the engine computer to fail, but if they do, you can install one of the older external regulators. It will do a dandy job of running the alternator, but on most vehicles, the "Check Engine" light will stay on and the diagnostic fault code "alternator field not switching properly" will be in memory because the computer monitors current through that field circuit. The light comes on when the fault code(s) could have an adverse effect on tail pipe emissions. Low charging system voltage will cause injectors to fire late and spark could be weak. Even though these things won't really happen once you have the external regulator installed, the computer doesn't know the system is working fine. It just knows the monitored / unused circuit is dead. Check out the diagrams (Below). Please let us know what happens.
Was this
answer
helpful?
Yes
No
+5
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
ROOFERMAN
  • MEMBER
  • 1 POST
  • 1990 DODGE RAM
Voltage regulator where is it located?
Was this
answer
helpful?
Yes
No
+1
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,128 POSTS
THis could be a tricky one. Chances are it is located on the firewall under the hood and looks like this:


https://www.2carpros.com/forum/automotive_pictures/249084_reg_5.jpg



If you don't see one, chances are it's an integral part of the computer.

Let me know what you find and if you have other questions.

Joe
Was this
answer
helpful?
Yes
No
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
MPMPMP41619
  • MEMBER
  • 2 POSTS
  • 1990 DODGE RAM
  • V8
  • 2WD
  • AUTOMATIC
  • 100,000,000 MILES
I have a 1990 dodge ram 200? Where is the voltage regulator located at? And how do you check it? Can you some how get me a picture of where it is too?
Was this
answer
helpful?
Yes
No
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,727 POSTS
It lives inside the Engine Computer. Use an inexpensive digital voltmeter to measure battery voltage while the engine is running. It must be between 13.75 and 14.75 volts.
Was this
answer
helpful?
Yes
No
+2
Wednesday, June 23rd, 2021 AT 7:09 PM (Merged)

Please login or register to post a reply.

Sponsored links