I have a 2004.5 Ram w/ 6 spd. that has been going into limp home mode w/ the P0146 & P2121 error codes. Finally bit the bullet & had the APPS replaced, but it did not fix the problem. My truck does not stay in limp mode forever - it will act up for a day or two & then be OK for a week or two.

This is really beginning to aggravate me. What else should I be looking for?

 

I have the same truck and had the same problem recentlly. After replacing the APPS twice and the ECM a couple times I ended up having a Dodge dealer replace three wiring harnesses. The harnesses seems to have fixed the problem for good. I was lucky to go a couple weeks before without problems and now that the harnesses have been replaced I have been good to go since June. The mechanic at the dealer told me that moisture getting into connectors creates resistance and ends up ruining the connectors by creating heat. I talked to one person after my truck was already apart that said he had the same problem and fixed it by unhooking the batteries and spending all weekend unplugging and cleaning every electrical connector he could find. If you want some more info PM me and I'll give you my phone number. Replacing all those harness cost me a lot of money so I'd try the cleaning thing first if you have the time and patience.

 

I’m $6,000 into a new tranny and I’m still having intermittent problems. Any additional info would be great

 

I had mine act up twice with the p2121 code, I replaced the tps and have not had any trouble since,but I did read somewhere that the two big harnesses on the the firewall drivers side was an issue of moisture and dirt getting in. I cleaned mine with electrical cleaner and use electrical grease on the connections.

 

check the wire down at the a/c compressor mine was chaffed and causing problems , crawlwd under truck , moved wire around tried it out, ran good installed spiral spaghetti wrap about 6/8 years ago still runs like a champ,,;;