Hello all,

I'm new to the forum, but you have helped get me through a few simple fixes on my 2001 Chrysler 300m. However, I am currently stumped and was hoping I could get some assistance.

About 4 weeks ago, my car went into limp mode and was only showing 2nd gear on the instrument panel. With your help, I changed the output speed sensor and while I was there the input speed sensor. This corrected my problem and I was good for about 3 weeks.

Last week I turned on my car and all gears were lit and check engine light as well. I got error codes p0601 for PCM and p1684 for battery disconnected. So, I ordered and installed a reprogrammed PCM to my VIN and mileage. After the installation, the check engine light turned off but the gears were still all lit. I turned off the car and started it again and everythinig looked back to normal. My car shifted and I took it for a short drive around the neighborhood. Now happy to have my car back, I put everything away and went inside. The following morning when I started the car back up, all gears were lit up again and now the speedometer is jumping all over the place. The only code I'm getting is the p1684 for battery disconnected.

Any ideas or help so that I can get back my car back up and running would be appreciated. Thanks for your assistance in advance

 

A common cause of electrical issues is battery connections. On the 300M there are also connections at tha "jump post" and ground at the fender stud. Disconnect and clean all of these connections even if they "look ok"