So I bought a 98 ram 1500 with 98k miles on it and the motor is great. Knew it had some kind of electrical problem when I got it the radio was out and the radio looks like it has an extra set of wires? I don't know though I work on houses not cars. So anyways I didn't care its a work truck.

Until I had problems with tranny a week after I bought it and was trying to scan for codes and obd2 didn't work since its on shorted circuit. IOD apparently. So I replace fuse just in case, no luck. While I was checking fuses under hood I notices the hood light flickering when id bump car. Could be bulb I'll check when I can.

Anybody know where to start checking voltage? Like what iod components are in which order I'm terrible at reading these diagrams. Maybe there's a simpler one? Thanks in advance I'll check back often before I pull my hair out.

Ps I've looked at all the wiring harnesses and looked for obviously stripped wires and grounds on parts that touch metal like the door jamb, under the seat, etc. Someone said sometimes it's the seatbelt module under middle seat? I don't know how to check it, its enclosed. Maybe I should just pay someone, but I'm hard headed soooo... Here I am. Thanks.

 

I see fuse 12 missing in the junction block, is the fuse blowing when you replace it ? That fuse does power a lot of things including the OBD connector and the underhood lamp. It also provides ignition off power to the radio for the memory etc. Seeing the "creative wiring" around the radio harness I'd start there, the pink wire going to the grey 7pin connector is fed from fuse 12. See if any of the added wiring is shorting it. Anywho here's what is powered via fuse 12: Underhood lamp, left/right visor vanity lamps, overhead map/courtesy lamp, overhead console, OBD2 port, glove box lamp, radio, power mirror, seatbelt control module, dome and cargo lamps. It also goes to the ignition switch for a "halo" which I guess is a lighted ring around the ignition lock on the higher trim levels.