Altenator Going??????? Please Help

Drains are so much fun!

Basically you have to isolate harnesses and find what's shorting to ground. It doesn't have to be a frayed wire, it could be a light bulb or a body control module, etc. If you aren't good at that stuff it's worth letting a shop do it.

With the truck shut down and pull the fuses to the ECM, stereo and any other clock, you can take the main negative off the battery. Then touch it back to the battery post and if you see a spark there is a drain somewhere.

 

I had a charging problem with my Marmon that plagued me for months before I could pinpoint it. Replaced just about everything under the sun including batteries, cables, starter etc. Took a shot in the dark and made up a short section of battery cable and ran it off of the ground post on the back of the alternator down to the frame and the problem was solved.

 

Could you explain it again for dummies. I couldn't understand what you have done exactly to fix the problem.
I have same problem which is battery voltage shows 11.7 to 12 but alternator produces 13.7 on idle. Battery keep getting drained not charging well. Thank you!

 

I used a section of new leftover battery cable I had and put some round ends on it like in the pic and ran it from the alternator straight to the frame rail. You can attach it to the bracket or anywhere you want to on the alternator as long as it is making contact with it. It was a shot in the dark but fixed the problem

 

Thank you. I'll do that tomorrow and let you know what is the outcome.

 

I read either here on a really early post or on the heavy haulers resource group or hhrvesource.com a comment on this very subject. The discussion placed great emphases on grounding, especially at the alternator.

 

Cleaned and tightened battery, starter and ground connections.
Added ground cable between engine and frame, between cab and frame.
Now it charges 13.4 wich is I still have a load or short somewhere.
Thanks guys for your help.

 

It did not work on me. Thanks bro for the hint.

 

Post #16 I printed some of the thread on grounding the electrical system. When I find it I will put some info on here telling where to go to read the info mentioned.

 

look for threads - 2005 vnl670 low voltage warning
and volvo vnl 670 bunk a/c and heat quit working
check volvo service bulletin 370 .01
look on the hhvresource for the shop manuals