Ok, since I can’t seem to find a good forum for the Expedition, I thought I would try here for some help. I’m sure the drivetrains in the Ex and the F150 are similar. I have an 04 Expedition 5.4. The car has been off the road for about a year and parked. I am currently trying to get it in shape for my 16 year old son to drive.

First, of course I have been repairing vacuum leaks for the last few years we were driving it and I think I have that under control…..for now. No lean codes have popped up on my last test drive. Here’s a list of the troublcodes that were logged that have me confused on where to start.

instrument cluster codes
B1318-battery voltage low. I did disconnect the battery to clear codes and start fresh. But this is still there. Battery is 6 months old and I have had to jump it if it sits a while.

B1352-Ignition key in circuit fault. I read up on this a little and I am thinking this may be causing my battery drain? Just not sure where to start.

B1255-External air temp sensor circuit open. Would this have anything to do with why the vents for the AC will not switch? I put the AC control in Auto and my vents stay in defrost position. Even when I try to control manually. I was thinking it could be another vacuum issue.

U1262-Data link fault. Did this appear because I disconnected battery?

Thanks for any insight everyone.

 

Also the temp gauge in the cluster doesn’t work. On my test drive, my scanner allows a live reading and all temps were normal. 160-170*

 

should be 190-195 at full operating temp.

 

not an expert, but if I were you I would have battery and alternator tested. Assuming they pass and battery is fully charged: clear codes and then go on long test drive, see what codes pop up and check your battery charge a few times while out test driving.

in other words, try to see what codes/problems you have that are not related to depleted battery.

Get a battery cutoff switch so you can easily disconnect/reconnect battery until you get problems sorted out.

searxh up on parasitic battery drain testing (here and YouTube).

 

I just got back from a long drive(40 mins), highway and some stop and go. Engine temp never went over 183 and that’s when I was on it pretty good running about 85 for 15 secs. Air temp is 73 here. I cleared all codes before driving. Still have the same codes. One new code. C1920 parking aid code for memory circuit problem.

Its running fine with no check engine lights but I just wanted clarification on the others.

As for the battery, I’ll probably get that tested I just don’t trust the kid at the counter most of the time trying to sell me a new battery.

 

sounds like you have the wrong tstat.

what was your battery voltage before starting engine up for testing and what was it when you finished test drive and shut truck off?

 

I didn’t check the voltages nor was I logging it in my OBD2 app. I’m gonna change the battery out of my 2500(sorry Ford guys) and see what happens. I think they are the same series battery.

But, I did go out and started checking some vacuum lines and I found the problem with the AC vents. And guess what? When I fixed that and verified they worked, ALL codes disappeared! But I was only idling it in the shop and didn’t take it out on the road so maybe they reappear.

 

Definitely think you should get the battery and alternator tested like laterongc said. That said, I expect you'll have to replace on or the other. And, I wouldn't do anything about the other codes until then. But, I suspect the temperature sensor that feeds the instrument panel and your OBD reader is defective. I don't know which one it is though: could be the ECT or the CHT sensor.

Let us know what happens...

 

The battery issue ended up being bad crimps on the cables. I have that taken care of and seems to be ok for now.

I had a vacuum issue causing my dash vents not to operate and I fixed that and thought I had everything taken care of. All was well for a couple drives but now the dash vents stop working when I am accelerating. So there’s another vacuum leak somewhere and I can’t seem to find it. And another issue has popped up. The temp gauge on the dash is pegged all the time and doesn’t respond at all. Any ideas?