Folks I’ll start with a little background. I have had very little issues with my 2004 6.0. At 192K I decided to go ahead and do Head gaskets,studs,oil cooler,HPOP and a few other items. The shop that did the work was a local I was trying to build a relationship with but I wont be going back to for other reasons. But after the work was done I kept getting an intermittent ABS light. I dont drive the truck often at this point but was trouble shooting when I could and it was intermittent in nature so did not make a final diagnosis. Now however I have discovered through the Battery voltage light illumination that what it appears is I have 13.1-13.2 volts at the ECU or where the voltage is read where the BullyDog GT I have is reading, yet at the Alternator output bolt I am reading 14.4-14-5 volts. So not sure if there is a missing or poor ground I am not aware of as Ive checked what I can find. I am assuming that with this voltage issue it may be related to the ABS light being illuminated as its the first low voltage item to be shed to conserve electrons. I am wondering if anyone else has experience with this issue. Thanks in advance for any insights provided….

 

It's possible. Do your roads get salted in winter or does you truck have a lot of rust? There is a TON of good info in the link I have attached. B.

https://www.ford-trucks.com/forums/1...tery-life.html

 

Be sure to note the voltage at the same time because as the battery and under hood temperatures go up, the voltage regulator should drop to a 13.6-13.8v range. Without addressing the stock condition, be aware the PCM reading can be down by 0.5v from alternator output.

As LB noted, I’ve got multiple videos about the grounds.

The code for the ABS setting would be most helpful, but with rework it’s possible for the switch connection at the master cylinder or ABS ground next to the radiator on the drivers side could be wonky.

A poor connection at one of the three connectors at the PCM can also give a lower voltage.

 

Unlikly as I live in LA (lower Alabama) so no salty roads. But thanks.

 

I will watch the videos ASAP and will check those connections as I have found several items I would classify as a lack of attention to detail after the work was performed. Part of the reason I won’t be returning to the shop I used for the work. I appreciate these responses and when I get home from this shift will try to see what I find and post results. Thanks again.