I am working on putting a 04 CTD from a T-boned 2500 into a 2000 Ford Excursion. I have everything working except the tranny. The torque converter locks up immediately when I shift into D and the engine stalls. I cut the wire to the torque converter and now the truck is stuck in first gear. When the truck is in limp mode the transmission is stuck in third. I have two codes P0882 and P0720. P0882 is transmission relay 12 volt circuit low and P0720 is output speed sensor error. I had to replace the original ECM and I was thinking the replacement ECM was possibly the problem, but I had it checked and I was told it was fine. I have tried three different output speed sensors, I took off the valve body and brought it to a transmission shop and they said it worked perfectly. Any ideas?

Thanks
Jake

 

Welcome to the site. Wow, that sounds like a great project. It'll be a real beauty when it's done. I think it's a really minor problem you've got now. I'm thinking maybe you've just got a couple of wires mixed up on the main transmission connector. Could you possibly have a bad wiring diagram? (I know, it's easy for ME to say, and you've probably been going over this for hours, but it's all I could come up with.) It would help if you knew someone with a scanner so you could see if there was any rational data coming from the transmission sensors.
Happy New Year.

 

If I recall correctly, the only wires I messed with on the transmission connector were the 12v supply to the transmisssion relay and the O/D wire which I have not hooked up yet. I think the rest go straight from the ECM to the tranny. When you mention a scanner, are you meaning the DRB 3 tool? I've got the OBDll code reader but it just gives me the codes mentioned above.

 

I was thinking of either a DRB 3 or an aftermarket scanner- Snap-On, OTC, etc. Any of them should give you a decent data stream for the trans sensors.

 

If I recall this correctly the tranny output speed sensor is mislabeled a bit because the tranny controller reads the rear axle speed sensor as primary info. The ECM doesn't care about the tranny, the PCM does.

HTH

AlpineRAM

 

Have you double checked all your grounds? I know that they can cause a mess of problems.

John

 

Trans is defaulting because you cut the wire,its not sensing the resistance of the lockup soleniod,thats why its stuck in 1st gear.If you want to fool the PCM into letting you go thru the gears,but without lockup,start the truck with the lockup wire connected,then interupt the lockup signal once its running a few seconds,and all should be good to test.The 02 and older ones would fall for it every time,hopefully the 04 is the same.

 

I tried starting the truck with the lockup wire connected today. I tried it on the hoist first just leaving the wires connected the whole time and no change. I also did a road test and I'm still cruising in first gear and that's it. I'm back to questioning whether my replacement ECM is for an auto trans. I called 2 Dodge dealerships with the part number on it and both told me that number does not come as a Dodge part for an ECM. Anybody know if that makes any sense?

 

Could it be a cummins part number? Try typing it in here http://www.dieselpartusa.com/parts.htm