I have a '94 Dodge Dakota, 318. I just rebuilt it about a year ago, 266k. I converted to a manual at the same time. I checked out the wiring diagrams in the maintenance manual and didn't see any reason why the auto ECM wouldn't work. I changed what wiring I needed, disconnected the OD button on the dash and everything worked great until about a month ago when the engine just DIED. The speedo and tach both dropped to 0 even though I was doing 70+. All the other gauges continued to work....oil gauge dropped to L when I depressed the clutch obviously.

Troubleshooting revealed that the 8VDC reference for the camshaft, crankshaft, and speed sensors was dead at the ECM. I have 12VDC in and the 5VDC output for the other sensors is there, but no 8VDC. The maintenance manual got me that far, but then it told me to "continue running the diagnostic with the DRB scan tool". Well, guess what, I ain't got one.

I would like to fix this without taking it to a shop so they can charge me $75 or more just to scan the thing. I did the back door code thing (ignition on, off, on, off, on count "CHECK ENGINE" light flashes) and it threw two codes that I can't find in the maintenance manual. (45 & 37).

Any ideas would be appreciated. I don't know where to go other than the ECM and I don't want to spend the $200 on that if it is something relative simple and much cheaper.

 

code 37 is the torque converter clutch/ neutral safety switch. youll get that code because its no longer auto. there is no code 45, are you sure it wasnt 44 or 46? the codes can be found here: https://dodgeforum.com/forum/1st-gen...ml#post1472415

generally the truck will run with the original computer for the automatic in it, but it wont like it. the computer in your truck is designed for an auto tranny and by changing the tranny to manual, it will cause the computer to throw codes. best bet to make your truck run properly again is to buy a manual computer

 

37 - trans temp no change, *or* torque converter clutch problem, *or* park/neutral switch stuck in park or in gear
45 - trans governor pressure problem
These two codes have to do with the fact that, well, the automatic transmission isn't there.

Your problem lies, apparently, with the lack of voltage coming from the PCM/ECM (whatever you want to call the computer) on the 8V circuit you said. Since you said this 8V provides power to the crank and cam position sensors. yes, without input from these, the computer will not allow the engine to run.
First, disconnect the battery. Than, disconnect the connector at the computer. Inspect for any corrosion, missing/bent/damaged pins on the connector and computer.

 

and do that... i forgot to add in that part =/

 

I did the swap about a month ago and my truck is still running great. The computer threw all the transmission related codes, just like I thought it would, but the only thing I had to do to get the truck to function properly was ground the park/neutral safety switch. I seriously doubt your problem is related to the swap, probably a faulty sensor somewhere that is unrelated to new transmission. Coincidences do happen.

I do have one question that came to my attention (but since your truck did run I don't know why this would be a problem)... did you put in the crankshaft position sensor for the manual, cause it is different.

 

is it different? cause i figure if it was a huge deal, the truck wouldnt run right or wouldnt run at all right from the start right?

 

Thats why I said that. I doubt it is the problem, I was just trying to eliminate something obvious.

 

makes sense

 

OK. Where the heck are ya'll getting these codes? I have the manual from Dodge and couldn't find either one of those codes.

 

Thanks. I didn't think it was related, but wasn't sure if maybe something burned up the ECM by not being attached or something shorted somewhere. I did swap out the crankshaft position sensor and grounded the park/neutral safety switch. It ran good for about a yr.

OK. Next question then....I went to Advance Auto to get a manual ECM and they wanted to know what kind I had in the truck or needed the VIN number. I told them neither would help as the truck was originally an auto. Does anyone know what the difference is and then, how do I figure out which ECM I need?