I think my PCM went bad!

[Sneaklylilpetey]

Went out today to start the truck that's been sitting for a month or so. Haven't driven it much because of the insane diesel prices in this country. I had battery tenders on both batteries.
Put the key in the ignition and I noticed that the P N R D 1 2 display was not coming up, Just showed the mileage. I turned the key over and it fired up then died after 2 or 3 seconds. Tried it again and same thing. Double checked the battery connections and tried again, same results. Tried one more time and now it won't even start, just cranks.
Hooked up the ODB device and scanned it and sure enough I'm getting the U0100 code. Not what I wanted to see.

**EDIT**
OK scratch that. I went back out to try and start it after posting this and it wouldn't start again. I left the key in the ignition for maybe a minute and then the gear selection display lite up. Turned it over and it starts right up. This is the weirdest truck when it comes to electrical issues, like it has a mind of its own. Put the OBD reader back on its not throwing any codes.

 

[Ozymandias]

If it happens again, lock and unlock the doors and then try starting.

And if one really needs it, one tender is enough as the two battery's are in parallel acting like one big block.

I do not use any tender as they tend to slowly boil the battery dead. I disconnect them and that's fine for up to 6 month storage in moderate climates.

 

[Topzide]

Get a newer smart charger. They will maintain the battery better than the old type! You can make a setup to keep them charged without opening the hood. Get a trailer plug for the 7 way and connect to 12 volt + and ground. Great option to charge batteries without opening the hood and truck sitting for extended time! Might want to add a polarized plug to prevent destroying cable! Ask me how I know!

 

[endoscott]

Hard to even find a decently built charger or maintainer. I have had better luck with NOCO stuff, but one of their maintainers wouldn't function correctly on my tractor battery. At least they have decent warranty. The Walmart ones only carry 3 month warranty. Never worked out of the box, got so hot it would almost burn your hand-on a brand new AGM battery. Went to return it when we got back from the desert but it was past the 23 months.

 

[Sneaklylilpetey]

It happened again this morning. It's been sitting for a couple weeks so I thought I would drive it. It started up with fine with all the dash lights on as normal. Then it died and the drive/park indicator lights went off. Tried locking and unlocking with key fob but that didn't work. Tried leaving the key in ignition in the on position for a couple minutes and that didn't work either.

I'm going to replace both fuel filters and drain the water separator when I get home. I think the PCM/ECM is taking a crap

 

[Regcabguy]

Check your batteries and charging system with a multi meter.

 

[AH64ID]

What year? Security key?

Get a newer smart charger. They will maintain the battery better than the old type! You can make a setup to keep them charged without opening the hood. Get a trailer plug for the 7 way and connect to 12 volt + and ground. Great option to charge batteries without opening the hood and truck sitting for extended time! Might want to add a polarized plug to prevent destroying cable! Ask me how I know!

The newer NOCO’s are pretty awesome. Integrated temp compensation and once the battery is fully charged the charger shuts off until the battery voltage drops, then it tops it off again.

 

[endoscott]

Yes, they do all those things, IF THEY ARE WORKING CORRECTLY!

 

[AH64ID]

Yes, they do all those things, IF THEY ARE WORKING CORRECTLY!

Well yes, but you can say that about everything.

 

[Sneaklylilpetey]

I ended up sending the ECM off to get tested and repaired if anything is wrong with it, $300 for that. I expect something to be wrong with it since I've had U codes that come and go recently.

 

[Sneaklylilpetey]

Got the repaired ECM back today from AutoComputerExchange.com. No details as to what repairs were done, just that it was repaired.
Popped it on the truck and started it up and she died. Started it up again and ran smooth. Cleared all codes from it and started it up again and ran smooth. Took it for a 20 mile drive and didn't get any weird gauge issues or engine codes like I normally get. Going to drive it every day this week just to make sure everything is good.

 

[nibroc]

sounds good sneakypete