P0601 code on 2012 Z71

kcult

Wish you were closer
Charter Member
Supporting Member
Multi-Factor Enabled
Joined
Dec 17, 2016
Messages
20,138
Location
ChesCo SC
Rating - 100%
54   0   0
Was just about to Conway today and was at a traffic light. Light turns green and I start inching forward. No sooner than I start to give it gas, the engine shuts off. CEL and traction control lights come on. Stabilitrack (or whatever it's called) is off. Luckily, I had enough momentum to coast into a divide.

I tried several times to crank it, but it wouldn't even turn over. After I removed and reinserted the key, it cranked. I drove it to the nearest lot and parked.

I got out ye ole code reader and it said P0601 internal control module. A quick search said either the PCM is not receiving the correct voltage, or it's bad and should be replaced.

After abandoning our mission, the goal now was to make it home without AAA's help. We did, but I noticed the voltage gauge was showing way less than 14v (not sure at this moment what it's supposed to show). Over the next hour, I saw it climb to 14v only one time, but slowly fell to about halfway the between the hash mark and 14.

We pulled over in Blenheim for some gas station chicken. When we left, the gauge was reading over 14v, but within just a few miles, settled back into its previous halfway position.

Alternator? I want to think so, but why would the engine shut off?

This was cruising about 60mph.

20200801_163731.jpg
 
Alternator and a weak battery?

Edit:
Reading the interwebs, the battery thing is a Longshot. Probably a bad or PCM or one of it's modules, or possibly a wiring issue with the PCM...
 
Last edited:
Alternator and a weak battery?

I'm leaning towards the alternator, since the battery is only a year or slightly older. I know that doesn't mean it's not bad.

Guess I'll be checking out both of those.
 
The alt low voltage should have turned on the “battery” icon in the cluster if it was putting out below 12 volts.

I have replaced a few bad pcm’s due to internal failure with the P0601 code. That model could very well have a pcm controlled “on/off” alternator giving you the wonky voltage gage readings
 
The battery shows about 12.5v. When cranked and idling, it climbed as high as 14.95v, but seemed to hover more in the 14.5v range.

I let it run for almost 10 minutes. The volts would only dip when the fan would kick on. And with it in drive and the brake pressed, it hovered around 14.2v.

Can I assume the charging system and battery are fine (as much as I'm not happy about that)?
 
The battery shows about 12.5v. When cranked and idling, it climbed as high as 14.95v, but seemed to hover more in the 14.5v range.

I let it run for almost 10 minutes. The volts would only dip when the fan would kick on. And with it in drive and the brake pressed, it hovered around 14.2v.

Can I assume the charging system and battery are fine (as much as I'm not happy about that)?

Sounds like the alt is doing its job, the battery is fine also.
 
The alt low voltage should have turned on the “battery” icon in the cluster if it was putting out below 12 volts.

I have replaced a few bad pcm’s due to internal failure with the P0601 code. That model could very well have a pcm controlled “on/off” alternator giving you the wonky voltage gage readings

No battery icon. Just these, then the engine shut off.

20200801_181033.jpg
 
This was also displayed, except they both indicated "off." At least that's what I think they both showed.

20200801_181216.jpg
 
This was also displayed, except they both indicated "off." At least that's what I think they both showed.

View attachment 234818
The abs module more than likely has “lost communication with pcm” causing those light to come on and scroll that message. A cheapy code reader wont access those modules to show you those code. They will be U codes along with module specific codes
 
Last edited:
Could something have happened to the truck to cause a poor connection? I ask because my 2015 Equinox recently became undrivable with similar indications, but I knew the reason why: my dogs chased a chipmunk up under the rear axle area and went Full Rambo trying to get the critter; they ripped out the rear harness and part of the main harness together with connections to the ABS module. I must have picked up a bushel of wiring and connectors out of the driveway. Not drivable. Replaced main and rear harnesses (not me, my body man). Did you know you pretty much have to disassemble the entire car to do that? Doors off, seats out, headliner out, everything. Got that done and the dogs ripped off the wire to the right rear ABS. Driveable but with codes. Now all fixed. Anyway, if all that stuff ain't getting a good connection, your vehicle is gonna act up or shut down. PS chipmunk got away, but looking somewhat second-hand.
 
Could something have happened to the truck to cause a poor connection? I ask because my 2015 Equinox recently became undrivable with similar indications, but I knew the reason why: my dogs chased a chipmunk up under the rear axle area and went Full Rambo trying to get the critter; they ripped out the rear harness and part of the main harness together with connections to the ABS module. I must have picked up a bushel of wiring and connectors out of the driveway. Not drivable. Replaced main and rear harnesses (not me, my body man). Did you know you pretty much have to disassemble the entire car to do that? Doors off, seats out, headliner out, everything. Got that done and the dogs ripped off the wire to the right rear ABS. Driveable but with codes. Now all fixed. Anyway, if all that stuff ain't getting a good connection, your vehicle is gonna act up or shut down. PS chipmunk got away, but looking somewhat second-hand.

Nothing obvious has happened to the truck. It mostly sits in the yard until its time to take the trash to the dump or if we're going somewhere that we can take the dog. And since we sold our camper, it sits even more.

I'll start poking around today to see if find anything obvious. I hope I do because I have trust issues when it comes to dealerships and our local garages.

Oh, and if it just threw codes, that would be one thing, but shutting the engine off in traffic? Can't have that.
 
Indy shop said PCM quit communicating. They found two corroded terminals and said they cleaned them up. But they advised if it did it again, I may be looking at a PCM replacement and programming.

Although it didn't "do it again," the CEL was lit the next day and same P0601 code was read. The other two lights didn't illuminate and the engine still ran.
 
Back
Top Bottom