Weird charging "problem", maybe??

[Fire Marshal Bill]

I've had my truck now for over a year. I've always thought the windows rolled up a little slow and the headlights were a little dim. I just wrote it off as being an older truck thing. My wife needed to drive the truck last week so i was without it until this weekend. SO, I get in and roll the windows down and man they were movin'. I rolled them back up and down a few times thinking "that's what i'm talkin about". Night time rolls around and my dash light are practically blinding me and my headlights are shining into eternity it seems. I watch the alternator guage jump when i accelerate to levels i've never seen before (not all the way to 18 though). Now i start worrying that something may actually be wrong, . Need ya'lls opinions on this. Do you think it may be overcharging or did something magically just go back to normal?

 

[cerberusiam]

You need to check the volts across the battery to verify it is not too high or you will be replacing all the bulbs and other fun stuff. Off the top of my head the max voltage across the battery should be 14. 5 volts under a load. Somebody else jump in if that number is wrong.

 

[HonkinDiesel]

It sounds like your regulator is shot or shorted out, so you are seeing full alternator output. As cerberusiam said, check the voltage at the battery terminals and rev the a engine a bit using a multimeter. You shouldn't see any more than 15 Vdc maximum.



If you are getting great voltage swings then you might just want to replace or rebuild that alternator.



Good luck and let us know how it goes!

Pete

 

[paccool]

Uh, what year did they drop the external regulator and put it in the PCM?? I think it may be the 91. 5's but I'm not sure. If it is, then you are probably getting close to a new controller (kinda like an ECM but it doesn't control the engine, just accesories like alternator, A/C, cruise, etc.



On my 93, the tach lead was not working and it turned out to be the PCM was bad. They run about $235 from the dealer plus a core charge. It is located under the front left fender close to the battery.

 

[Bob Beauchaine]

Sounds to me like your wife couldn't see to put her make-up on - so she fixed it for you :-laf :-laf



Bob

 

[Fire Marshal Bill]

the battery was dead this morning. Have a mechanic friend coming by to check it out today. Sounds like it's the voltage regulator, i just hope it's external and i haven't fried too much stuff.

 

[Fire Marshal Bill]

Okay, the more i search and read on here, the more it's looking like the PCM. I have been having OD issues too. No a/c problems except that i can't get it to blow colder than 60 degrees. I don't use the cruise control so i wouldn't know if it's acting up.



If i were to install an extenal voltage regulator, would my OD problems remain? Seems like i may need to go ahead and bite the bullet and replace the PCM. What do ya'll think? Where can i get the best deal on one?

 

[paccool]

You can get a regulator from an earlier truck and put it on the firewall. My son did this with his 92 and ran it for a month or so before the new PCM arrived. I wasn't involved but he said it was easy to wire up. He left it on the firewall as a backup in case there was any further problems.



Stan

 

[Fire Marshal Bill]

Okay, apparently i have an external voltage regulator and it has gone bad. We were getting 16 volts at the battery at idle. Battery shows signs of being heated up and is leaking . Disconnected the voltage regulator and check the voltage at the battery and everything checked out okay. Off to the auto parts store to get a new regulator now. Hopefully that's all it will take to fix things. Thanks for the help.

 

[paccool]

Glad to hear the problem is not a PCM. The regulator will be cheap in comparison!

Now, if the battery just hasn't been cooked too much!



Stan

 

[Fire Marshal Bill]

New regulator on and everything appears okay Oo. Will keep an eye on the battery, it was on it when i got the truck and only has 660 CCA so it's undersized anyway. Gonna save up my pennies for a Deka.

 

[HonkinDiesel]

Good to hear you got it fixed.

I put in BIG honkin 1200 CCA Magna charge battery in mine no problems with power now.

 

[RonA]

Converted the 92 to an external regulator. It uses one off a mid eighties dodge car. Seems to work fine but takes about 5 seconds to kick in when you first start up.