I'm pulling my hair out here. I bought an '02 7.3 excursion. Everything seemed to run and work fine when I bought it, have a bad #5 glow plug module that keeps popping up, but I'm pretty sure that it unrelated.

I put exhaust, intake and an edge attitude with juice in. My friend, who owns a custom diesel shop, did the work.

About 2 weeks after all work was completed, battery voltage was reading low on the truck. Took it in and had O'rielly test, it was bad. First alternator I purchased from them seemed to work for about 300 miles. On my way home from a long trip, started showing crazy voltage running through the battery and gauges would "sweep" and radio turned off. Seems as though they would do this whenever programmer showed 15.9 volts (which I assume is the highest reading it will show). Once voltage would go back down, they would come back on and work fine until the next time this happened.

Took it in to have O'Rielly test it, they said it was fine. I pulled it anyway and had them exchange it. Got the new alternator and installed, it never seemed to bring voltage up higher than 11.8. Decided I had had enough and am not real good with electrical, so I took it to the Ford dealer to have them troubleshoot for me. On the way (3 miles trip), everything shut down on the truck and had to have it towed .5 miles to the dealer. My wife was driving and she said the dash light up, then everything died including the motor. Figured batteries due to high, then low voltage. Ford tested and confirmed weak batteries, put two new batteries in and Dealer tested charging system at 11.6V under load indicating the alternator might still be a dud. Ordered a Remy alternator, waited for it to ship, pulled old alternator and put the Remy in.

Upon start up, everything was running great. I let her warm up and packed the truck for our weekend trip. Got in, realized I didn't have dome, head or cluster lights, guages were dead, power windows didn't work, no radio and no power driver seat function. Did some quick reading on here, determined fuse #35, #41 (I think, can't remember exact number) or possibly delay accessory relay (302?). Drove down to O'Rielly, purchased fuses and relays as we were trying to get on our way out of town. Put fuse #41 in that brought cluster and head lights back, then fuse 35, but it blew immediately. I installed the relay switch and it didn't do anything to change it either.

We drove it home, packed the other truck and took that.

I did heavy reading on here and other forums and determined it could be numerous things, but most likely, it was OD wire chaffing. Got home, pulled the lever, saw slight chaffing through shrink tubing, but not through that portion of wire insulation. Cut back and pulled off shrink tubing to see if maybe there was a small hole or something I was missing, nothing! I even pulled the dome light housing as that has been known to short, everything in there looks like it can from the factory. Also unbolted the fuse box to see if there was anything apparent with the wires coming into the box, but there is a lot going on back there and I am no expert. Didn't see anything blatant, except for the thick green wire coming off the ignition switch has been cut with a pretty poor patch job to put it back together, which I will make right, but am pretty sure that isn't the issue.

Sorry for the long post (my first ever whoohoo!), but my question is, Could the wiring issue be inside the shift lever tube so that I just replace the whole thing? If that's not plausible, does anyone else have an idea of what the heck is causing my problem? Battery saver on guage cluster, maybe? Thank you in advance for any help you all may have for me.

 

What does #35 fuse protect ?

Edit, also just to be clear. Did both # 42 and 35 blow again after replacing them ?

 

The battery saver relay is protected by fuse 35. The Interior Lamps relay coil is also protected by fuse 35 but the contacts of the Interior Lamps relay that power the interior light are on fuse 41.

This is what I found on here on another thread.

Edit to original post fuses in question are #35 & #41. Fuse 35 appears to be the only one that blows. I continue to have guage and head lights, but lights stay on after key is out and doors open (which should shut them off, correct?) this is with selector set on Auto. If I move to on/off positions, they do what they are supposed to do.

 

If I am understanding correctly the battery and alt issues are fixed, you have 12.8 volts on both batteries with the vehicle not running ( with the interconnect cable unhooked so they are isolated )

Interior lights which are protected by fuse 41 work and fuse 41 does not blow

Fuse 35 keeps blowing
Relay 302 has been replaced which is protected by fuse 35
Battery saver relay has not been changed and is protected by fuse 35

I'd say replace the battery saver relay next just for good measure.

I do not have an auto headlight switch on mine so I can not be certain but I think if your door is open the interior lights stay on.

I am pondering the issue and looking for a wiring diagram. I love a good puzzle ( when it isn't mine ...lol )

 

Your breakdown seems correct. I haven't isolated the batteries, but the voltage readings on the tune are normal and they have 5 miles on them and the truck has been started exactly twice with them so I assume voltage is good and yes, charging issues seem to be resolved.

I went ahead and ordered a new shift lever JUST in case the wires were shorting within the lever tube that I can't get to. I guess I can go try and grab a cluster from a junk yard and see if that fixes it, then send in my cluster to the company in NC that does the repair for less than the dealer if the battery saver switch is the culprit.

The only other issue I can think of is leaking windshield onto I believe the ECM which I've read can be a common problem as well. I'm not sure on how to check that, but here in CA the problems did start after our first real rain and windshield is still original believe it or not.

 

The battery saver and interior lamps relays are in the cluster. Those two relays control the accessory delay relay in the CJB which in turn controls your interior lights, radio, pwr windows, etc. Check out this thread https://www.ford-trucks.com/forums/9...s-radio-4.html

 

Fwiw, I have a bully dog gt that plugs into the OBD port and displays voltage. it is consistently incorrect. I don't know if that is a bully dog issue or an obd port thing but the voltage readings direct from my battery with a fluke meter differ.

Don't know about your juice gauge thingy but you may want to verify. When I was chasing a draw on my ex I spent awhile chasing my tail because I took the readings as correct.

 

Will do tomorrow Pirate. I would think I would see issues I saw on my way back from my last trip if voltage was not good, but I agree, it's probably best to eliminate the middle man on these issues. I emailed a local shop in Sacramento to see if he does the battery saver repair as the above thread is helpful, but I am in no way capable of doing that type of electrical work myself. I would prefer to avoid the downtime to send it out to the place in North Carolina. :-/

 

My cluster went out on my 06 and never blew a fuse and not all those posters have mentioned the fuses so I am not completely convinced yet especially because OP isn't reporting the gauges going wonky intermintly plus the OPs issue with the battery and alt.

But...being an electrical gremlin I definetly would not rule out the cluster as it was my first thought as well.

 

I was convinced I was going to pull the OD wires and find chaffing and be done with this today. Because they are ok, I am running out of things to "fix" with the symptoms I'm having. The cluster is sort of my "worst nightmare" as I was hoping it would be one of the quicker, less expensive fixes. The fact that this is my wife's ride and she didn't really want it in the first place is also putting me in a rough spot with the Mrs. since I can't get it to work properly. Lol

 

I feel your pain, my wife always wanted a Cadillac CTS so I bought her the CTS-v, for some reason she doesn't think 500hp is nessasary in a 4 door family sedan and takes every opportunity to tell me about it, especially when it needs new tires. Lmao

Don't despair, you will get this thing figured out and hopefully she will come around to understanding the true greatness of the Ex. Until then..Be extra nice to her, or hide. Whatever it takes. lmao

 

Thanks for your help. Hopefully the local shop can do the cluster, or you or someone else can hook me up with a few other ideas. She traded her perfect TBSS in for this so it's been a struggle. Haha

 

This is the shop that is discussed in that thread Shepard linked
2005-07 Ford Super Duty Instrument Cluster Repair | CBM
They list the 05 up cluster, next step may be to call them and discuss your issue.

 

Yeah those guys do the earlier ones too. We are supposed to be going on an epic road trip this weekend so I was hoping to take it. If that's the only option, I'll bite the bullet, send it out, and drive the other vehicle.

 

Call first thing in the morning, if they sound reasonably confident that is the issue ask if they can do a 1 day turn around and use overnight shipping each way. Worth considering, or it could just dig the hole you are on with the wife deeper.... Zero or hero kinda deal. Lmao