Hey good morning, guys!

So, got my new alternator and batteries installed on Saturday. Went for a drive to pick up some meds and as I was getting close (I was slowing down, coming up to a yield to merge onto another street), the engine just completely shut off. Put it in park, started back up and away I went. Voltage and everything seemed to be normal from what I can remember. Drove it Sunday with no issues. Went to the store this morning on the way in to work and noticed my voltage was reading in the mid 11s. Got to Walmart and checked voltage on the batteries: 12.8 on passenger side, 12.4, then 12.3 on driver's side, tested with a multimeter. Started it up and passenger side was reading over 14, driver's side was right around 12 (a little fuzzy on that though), and according to my app, voltage was 11.8.

So, here's the weirder part? Driving home, high 11s the whole time, then when I turned into my neighborhood, it's a little bumpy due to some road construction, I look at it and now it's in the low 13s.

So I'm thinking I may have some issues with wiring as the batteries and alternator are all new. would this probably be a battery cable issue, or are there other areas I should check? I just found this post (https://www.ford-trucks.com/forums/1...side-work.html) so I'm going to check those videos out when I have a minute, but just wanted to get y'all's thoughts.

Thanks!

I can take and attach an engine pic a little later today to give you guys a visual.

 

Cables or connector.

Attached would be a more appropriate video rather then grounds which was posted in your other thread, but take some pictures of your positive battery terminals and cables. It could be the alternator connector, or with this situation, "passenger side was reading over 14, driver's side was right around 12 " it sounds like it could be the positive interconnecting cable between the batteries.

 

So yeah, I definitely should have gone back to that video from when you posted it to my earlier thread

Everything looked good except for my I circuit. With the key on, I was getting 12.08V. Battery was showing 12.63. So if I understood the video right, it’s probably my harness? It looks like there are several different harnesses, which one should I look for? How difficult of a job is it to replace that?

i could probably use a wiring upgrade as well, but if the other numbers are good, that’s probably going to have to wait until after the harness. I’ll post pictures here shortly. Thanks for the help! Would have been super frustrating to get new cables and still have the same problem...

 

You might also want to watch the "Voltage Drop Test" Video on Youtube.

 

 

Hmm, ok. So what are you thinking then? Maybe not the harness but something else?

Here are the pics (there are a few)...

Passenger side







Driver side





Alternator





Also, another post I came across while I was messing with things last night reminded me I had some stored codes. A YouTube video I watched about the wiring harness mentioned some of them... I forgot to bring my code reader when I bought the truck, so I didn't notice these until afterwards.




Thanks for all of the troubleshooting help so far, y'all. Very much appreciated.

 

IMHO you need to start with a good cleaning of your cables at BOTH ends of where they connect and go from there. What is all that on the passenger side positive going to???

 

I do eventually plan on replacing the battery cables, but if those aren't the problem, they're going to have to wait until I get this voltage and randomly cutting out stuff fixed. Thanks!

 

It's all yours from here, Jack.

 

Roger on the cleaning. I'll take care of that today after work. As for that random cable running up (bottom goes to the other battery, right goes to the alternator), I need to track that one. I think I've looked before, but can't remember now.

 

First, this terminal connection jumps out.



P0620 is the code for voltage output not as expected. If you have dual alternators as I suspect due to the second cable with the insulated cover, it's more complicated.

And all the glow plugs are at issue. So you might have to visit the glow plug module and wiring too. Which brings up ......

You have a lot of weird things going on at once, and probably some history other then this thread. Brings up the changing of alternator and batteries.

First all the battery terminals need to get cleaned. And while all the terminals are off the posts you need to check for continuity from the cable I noted as the primary feed from the battery connection the top alternator, both the main post and the sense circuit at the connector. It's possible the fusible links are blown and some of the weirdness is the top alternator is not working while the dual alternator is. There are also fusible links to the glow plugs from this connection. That continuity check is the same function as checking for positive voltage at the alternator post and wiggling the cable to it.

You also need to check continuity from the repaired lug on the battery to battery connection to the drivers side positive connection, with it wiggled around. That may be the cause of the differential in voltage readings between the batteries you noted earlier. That repairing lug really needs to be replaced considering the amps passing through it.

I'm attaching some files from my 2003 service manual for the dual alternator. If your not good with electrical, this may be a shop repair.

 

Gee thanks. I owe you.

 

HAHA, I know, right??? And I know what paybacks are. I also know when to stay out and not confuse the situation any further than necessary. Your expertise is WAY more than mine in this area and much appreciated, I promise you. You don't even know how much money you've saved me in this area. I was just trying to state the obvious things until you arrived and laid it all out. Again, thanks for saving me.

 

I never miss the opportunity for comedy, even when it's only me that is amused. This .... will be complicated.


OP, I missed one while being overwhelmed.

P1148 ALT Generator 2 control circuit Charging system