Diagnostic Code PO601

[Runaround]

I have an 01 Dodge Ram 1500 with an automatic transmission and approximately 235,000 miles on it at work that is showing this code. Where is a good place to get a reman unit for this truck?
Also when you start it first thing in the day and start driving down the road it will start spitting back through the throttle body, from what it sounds like, and will continue to do this while loosing speed unless you floor the accelerator pedal to the floor momentarily , then it will usually run properly.
If you have driven the truck and let it cool off and drive again later I don’t think it does this. I think it runs properly. Would this be related? If not related what might be causing this?
The PO601 is the only code showing up.

 

[Joe w.]

I believe that code means there has been an internal failure in the pcm. Not sure what it is or caused it.

 

[GTyankee]

OBD-II Trouble Code: P0601 Internal Control Module Memory Check Sum Error

in case it needs to be replaced

01 dodge ram 1500 pcm - Google Search

 

[scrounge]

You might want to check the connections first. I had a '92 Dakota where the harness connecting to the PCM came loose after enough driving; some epoxy on where the bolt screwed in fixed that problem. Check where your harnesses connect. If they're okay, check the wires for fraying and loose connections. This might take a while.

As for a PCM, you might find one in a junkyard, but make sure it's for your exact configuration; year, engine, and transmission. There should be a number on the unit; make sure it matches the one on yours. It's possible that the unit can cross model years, as this generation was essentially the same from the '98 to '01 model years. No telling how long it will last, but it will be much cheaper than a new or reman unit, and you'll make any mistakes on a vehicle that's going to the crusher anyway. Some junkyards put their inventory and prices online.

The sputtering seems like a separate problem. When did you last change the air filter? My truck performed better after I removed and cleaned the throttle body, and replaced that gasket. Perhaps some plugs are fouled.

 

[Runaround]

This happens only when the motor is cold after driving it a little ways and getting it to run right it drives and runs perfectly.

 

[scrounge]

On older vehicles, it might be the choke pull-off rod is out of adjustment. Yours doesn't have one, though. I've read of this problem being caused by a bad temperature sensor, but haven't had any personal experience with one going bad.

 

[Runaround]

Update: The PCM has now been swapped out with a rebuilt one and a new fuel pump has been installed because the old pump quit just before the PCM swap.
The truck runs no different. I have driven it a little more and found out it does this spitting back every time the truck has sat for awhile, even about an hour.

 

[Runaround]

Help. Anyone with any ideas?

 

[SYKRAMMAN]

I know what I'm about to recommend is redundant but have you traced all grounds and connections for corrosion/burnt/melted/frayed/damaged in some way? Little things like that can cause a world of trouble especially on these third gens, take out the tipcm and check underneath for the green ooze known as car killers. It may take you a while but more often than not you'll find the issue and its usually corroded/ bad wiring, "usually"!!
Even check body to cab grounds, engine to frame, bed to cab, and also apply dielectric grease to ALL connections.

 

[Mister Luck]

I’ll second It’s a good idea to check the harness also as with PCM’s being sensitive to temperature and contamination you cont go wrong looking at all options.

OBD-II Trouble Code: P0601 Internal Control Module Memory Check Sum Error

 

[Runaround]

I’ve checked grounds, no issues found with them. The truck only acts this way if you turn it off for about an hour or more. It runs fine after you flor the gas pedal momentarily.

 

[Runaround]

whatever is causing this problem is not turning on the check engine light and I’ve checked, the light does come on during the bulb check when the key is first turned on. No light/no codes.