After trying to install my DP Tuner, my truck won't start.. with or without the tuner. After talking to a few people, I need to try & swap out PCM's & see if my truck will start again. I currently have a DPC-422 in a 2001 with an automatic. My question is, does it have to be an exact match for me to try the swap with to see if it will start?

The symptoms i'm having are the truck will crank, build oil pressure.. the tach does not move & there is no smoke from the tailpipe.. Also the fuel pump is not engaging when i turn on the key... I went thru all the fuses yesterday, numerous times & could not find a bad one..

 

anyone? ...

 

I would think a PCM off the same year truck would work as long as long as it has the same trans. I don't know for sure, I just think it will.

Man, good luck, I sure Jody can get you up and running. You will love it once it gets straighten out.

 

Well, my problem is.. I have 2 friends who have 99's.. but I don't know anyone with the same year as me.

 

You didn't have the key in the ignition while installing the chip did you? Fuel pump not coming on means the PCM is not being energized. I'd start by checking for any blown fuses, and swap the PCM relay for the blower motor relay in the fuse panel to be on the safe side.

As for the PCM, you're looking for a 3 letter and 1 number code like PMT2. That will be the number you want to match up.

 

No, I made sure not to have the keys in the ignition. I also checked fuses & swapped the relays (i'm at work now, so I can't look at the book.. are you referring to the ones in the fuse panel under the hood)

So as long as the code like PMT2 matches, the DPC-422 doesn't matter as much? I can borrow the PCM from my nephews 99 since its sitting with a hole in the block right now, but he doesn't know what PCM he has in it. I just want to make sure its safe to do so, so I can find out if it will start & the PCM is the culprit.

 

I'm guessing your PCM is PMT2, since that's what my wife's is on her 01. I'm also guessing, the 99 will have a different code, but yes, match that code, not the numbers you listed.

I don't remember what items they put where since my 02 only has the one fuse block, but check the ones under the hood as well as the ones under the steering wheel. Make sure to check the fuses with a test light. Sometimes a fuse can look ok when it's not.

If all you're fuses check out, remove the connector from the PCM, look it over, and plug it in again. What does your wait to start light do when you turn the key on?

If the keys were out, and the fuel pump is not coming on, it's likely something simple that is keeping the PCM from powering up.

 

I agree Chris. I think it is something simple that is over looked here. I have the PMT-1 in my truck. I also think this is a fuse thing, but I can't put my finger on it.

 

So if the 99's codes don't match, I can't use it to test mine correct?

I've had the PCM out numerous times, checking pins, etc... The wait to start light comes on just like normal when i turn on the key & it eventually goes out.

If the PCM is fried, would it send info along to energize the fuel pump? The only things I can come up with is I remember reading if the connections are not clean enough it can mess up the PCM. I also read about static electricity. My house is very dry since I heat with a woodburner & I cleaned the PCM & installed the tuner sitting at my desk in the gameroom. I don't remember any static shocks while doing it & I used nothing other than my fingernail, scotchbrite & a piece of rag with nail polish remover, but I am stumped here...

 

I thought that's what I would find as well, but she has (had) the PMT2. Her stock tune is now a PMT1 since Tony and Jody apparently like to tune off of the PMT1 code.

At this point, I would suggest finding the PCM codes of all the computers, then call Jody in the morning and ask him. He will be able to tell you for sure. Until then, I would not swap different PCM codes into your truck.

I can't answer about the static issue, but the fuel pump not coming on and the lack of RPM signal tell us the PCM is not powering up. Have you tried turning the key on (not start), then wiggling wires or pulling and replacing the PCM relay to see if you hear the fuel pump kick on? What about cycling the key on and off several times to see if the pump kicks on one of those times?

 

I'm still at work til midnight, so I'll get back to my truck 1st thing in the morning. I called Jody Saturday & his voice mail said he was in Washington doing live tuning til Tuesday. I did exchange a few emails with Diane though. I haven't really tried anything with the fuel pump.. I just learned about it this morning before i left for work & all i had time to do was confirm it wasn't running. But yesterday, i pulled fuses, swapped fuses, & I did swap 2 relays under the hood.. if I recall.. it was a PCM relay & the blower motor... and if I remember right, when i was checking the fuel pump this morning, I heard the blower motor running on low...

 

I know Jody is out on live tuning, but if you've been emailing the boss, I'm sure you'll get an answer to your question on the PCM codes.

Try cycling the key several times when you get home and see if the computer wakes up one of those times. You'll be able to tell when you hear the fuel pump kick on.

 

I don't know for sure about putting an older pcm in a newer truck, but I have a PMT2 pcm in my early 99, that had a XLE4 pcm stock.

 

From what I've seen most of the PCM's are interchangeable if they are the same configuration for TESTING PURPOSES. If you use an older PCM in a newer truck like mine, the guages won't work since they are bus communication and a couple of other things won't work right, but I've heard guys that have done this to test the starting.

The computer type and programming code are important. You have to stay within the same computer familiy, programming revisions can vary. PMT1 and PMT2 are programming code on a DPC 422 pcm.

For isntance mine is a DPC 462, and I can use vdh1 to nwm0 code.
Check this link for more info

PCM Codes - 1994-1997 Power Stroke FAQ

 

Thanks for the info Chris. It seems like I remember seeing a little difference in the pin out charts between the older and newer trucks, but never have spent the time to understand if the differences where important.