2003 electrical issues

[edyrlund]

New to the forum and hoping for some help, i found a few posts with similar problems but they had no replies. I have a 2003 2500 CC 4x4 LB with 5.7 hemi.
Recently the radio started to go off and on. Then the security light came on, there is no security system, this also made it so i could not use the lights, interior or exterior, or the power door locks unless the key was in the ignition and turned to run or acc. Once the key was turned everything worked but the radio. I checked all the fuses including with a multimeter and even replaced the radio, cluster fuse even though it tested ok. I also replaced the battery because it tested marginal but provided no change. I checked the radio plug and only had 4 volts with the truck running except for the wire for the lighting which was 12.4 I tried tracing wires but had a hard time finding where everything went. I finally got fed up without having a radio and ran a new power wire to the radio and it works fine but i would like to have the interior lights again and the door lock. Sorry to ramble just wanted to get all the info out there. Thanks for any help.

 

[ststock23]

I was logging on looking for info on the exact same issue! Some sites mentioned it might be ignition switch. Tried that but no change. Someone out there has to have solved this mystery before!

 

[03hemi]

Maybe not much help but my 03 was having some intermittent no start issues and everything tested perfectly fine. Turned out that in the harness leading to the fuse box there was a simple, single corroded wire giving me an intermittent bad connection. Thank God it was a bright sunny day when I pulled the box and flipped it over and saw the green crud on a wire, looked closer and saw maybe one single copper thread left. One snip and a connector later and everything was fine again.

 

[Cahdah]

My old man has since got rid of the truck but he had a 04 5.7l quad cab 4x4. We would be riding down the road and that exact same issue would occur everyonce in a while lights wouldnt work and along with a lot of the inside electronics. Radio would just turn on and off randomly. Luckily it was warrantied up until the day he got rid of it because the dealership just kept changing the radios and it would fix it for a couple months. That truck ended up going through 4 stock radios until we bought an aftermarket pioneer. The pioneer had no issue for the 4 months we had the truck afterwards. That's my experience Good Luck!

 

[Redtruck-VA]

This problem is generally associated with a bad battery, corroded grounds and/or corrosion under the IPM. The factory left the bottom of the IPM open and especially 4wd that have been off road water and mud get up in there and corrode the plugs and wires. As mentioned, unbolt and flip the module over and clean it up looking for corrosion. Good luck....