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Discussion Starter #121
Also the other code shown (p1280) is because I unplugged the icp sensor

installed it back in and code was gone
 

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Discussion Starter #122 (Edited)
I am debating now if it could be the

PCM - I have the chip unplugged with still no results

IDM - tried off a similar 7.3 96 f350

IPR - should I change it out with one from auto parts store?

the batteries are drained so it was hard to tell what’s going on
suggestions??

am I supposed to always take the battery terminals off before I change out the IDM, PCM, IPR?
 

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The P1283 is the IPR Power Circuit. Perform the attached tests. I had this code on my 94 and it turned out to be the PCM not providing the ground to operate the IPR. You don't need the breakout box, just probe the pins on the PCM connector. Do the tests before throwing a PCM at it. Cheers!
 

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1st thing is disconnect the glow plug solenoid. That should slow down the battery drain problem a lot while cold cranking. Next, track down that short. P1747. A continuity test on the harness should rule that out, along with checking the solenoid.

Did it pass the buzz test eith old ICM or donor unit?
 

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Also, yes, disconnect you battery before swapping IDM or PCM
 

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Here are the pinpoint tests for the P1747. Cheers!
 

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Discussion Starter #127
1st thing is disconnect the glow plug solenoid. That should slow down the battery drain problem a lot while cold cranking. Next, track down that short. P1747. A continuity test on the harness should rule that out, along with checking the solenoid.

Did it pass the buzz test eith old ICM or donor unit?
the glow plug relay?
Yes it passed the buzz test with donor ICM

I should have checked with my ICM if it passed too! The CEL was because the ICP was unplugged NOT because of the ICM 🤦🏼‍♂️
 

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If there is any power applied to the PCM you can cook it when you remove the plug on it. It is more likely if there is a chip removed but when working on any electronics disconnect the batteries before working on them.
 

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Discussion Starter #131
If there is any power applied to the PCM you can cook it when you remove the plug on it. It is more likely if there is a chip removed but when working on any electronics disconnect the batteries before working on them.
good to know! Wonder if my IDM is fried as I removed it with batteries connected
 

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The problem usually doesn't come up unless the key is in the ignition with power to the affected part, but with electronics you never know.

It mostly happens with the PCM when a person removes a chip from it while it is under power. I haven't heard of a problem doing it with the IDM.
 

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Discussion Starter #133
The problem usually doesn't come up unless the key is in the ignition with power to the affected part, but with electronics you never know.

It mostly happens with the PCM when a person removes a chip from it while it is under power. I haven't heard of a problem doing it with the IDM.
makes sense, I fully charged the batteries so I want to test everything as shown; But my buddy has a pcm off his truck is it not going to work if I just unbolt the 10mm and clip in his pcm?
 

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If yours is a DPC-202 PCM and his is the same then it will work fine (I'm assuming neither of you has a MIF-series program). Cheers!
 

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In layman's terms, check the code on both PCM's. Or as long as your truck and your friends truck are both California models with automatics they will swap. But if one is a 49 state truck and the other is a California truck then they won't work.
 

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You could try it and see if it starts, but if you try it and it doesn't you should put your old one back in, clear all the codes and see what pops back up when you try to restart it again. Learn how to do the tests for the ones that do, and go from there. If you don't I think you are going to be chasing your tail. Cheers!
 

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Discussion Starter #138
Finally resolved this and it was the PCM! Fuel pump was also replaced and it seems to work fine! Im going to order a PCM from autozone and maybe get my original oem fried one sent out to get repaired if its worth it? What goes bad on these?

Thank you all for your help! Couldnt have done it without you guys!
 

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It seems like we are getting more threads about bad PCMs lately.

Maybe coincidence or could we be seeing these original units reaching their lifetimes?
 

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Glad you finally solved it! You will probably need to use you old PCM as a core for the replacement going with one from AZ or RockAuto, etc (so it would cost you the core charge plus repair cost to have that spare). Definitely easier to get a replacement, IMO. When mine went bad, I got one from RockAuto. I never had any problem with the replacement PCM and I think it is still going strong over 10 years later. Cheers!
 
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