Hey Guys!
On my way home the other night my truck stop charging. I pulled the Alt. and had it checked it passed with no problems. so I checked the fuse and found that the engine control module fuse was blown so I replaced it. still after that the Alternator still wont charge the batteries. Next the Tach was acting up also so I replaced the crank sensor. Well that fixed the Tach but it still wont charge the batteries. So I wired in a external voltage regulator. I hooked the blue wire to where the blue wire was at on the alt. and the green wire to where the green wire was on the Alt. and ran 12 volts keyed to the blue wire. I mounted the voltage regulator to the fire wall where I knew it would have a good ground. started the truck up and it is finally charging the batteries. The problem I am having is if you bump the throttle the GEN and check engine lights will flash on and off. this only happens when you bump the throttle. then after running for 1 min the GEN light will come on and stay on? I double checked the batteries and they are reading 14.88 to 14.90 while the truck is idling.
So my questions are:
1. If it is charging 14.88 to 14.90 is that ok or to high?
2. Is there any way to stop the check engine light and GEN from flashing?
3. Is there any way to get the GEN light to go out and not stay on?
4. Should there be a ground wire ran from the alternator to the regulator

Thanks
Eric

the truck is a 96 2500 5 speed manual eclb 4x4

 

Somebody? Anybody?

I ran a ground wire from the alternator to the voltage regulator. And found some pinched wires. This all took care of my flashing engine light and gen light.
Now the truck is charging around 14.50 and when you rev it up it charges up to 17.80 volts which is way to high I would think?
I plan to get a new voltage regulator tomorrow and try again. Any thoughts at all why my gen light is on all the time and why the voltage raises like crazy when I rev the engine?

 

I'm not a big fan of the external VR unless you have to. You will always have the gen light on because you have removed it from the PCM control. If you do the key on trick, you should have a code 41 or 47 I think.......

As for the overcharging, It could be the VR ( seems like lots of problems with generic VRs ), or over on the first gen area, there is a thread where they added a relay to correct the sense voltage that seemed to work.

 

I went with a ford vr, and it works great.no engine light ever came on.sounds like a bad vr....Robert