I’m new to working on trucks I’m currently trying to figure out if I’m having computer issues. Im constantly getting a code p1603 constantly l,I’m also having my trans temp light going on but the temperature isn’t a concern it’s running around 205 even when it’s on.I’m also throwing a code u0101 indicating problems with communicating with the computer or faulty battery or terminals but all of that is good. this truck was originally sitting for a couple years after the rear differential went out and had it replaced. now trying to figure out if I’m replacing my computer next or transmission next even though the transmission is shift good also the sensor for the transmission temp inside of the transmission?? Or do I need to replace the computer or both?? Thanks I have a 06 dodge Dakota v8 with a 355 ratio differential rear wheel 2wd

 

The battery may need to be changed. That's a common problem that creates weird issues with the computers and communications between them. Try changing it out with a known good battery and cleaning all corrosion off the battery terminals.

Are you using an obd2 tool to check the Trans temp? When I do that I get weird readings depending on the temp. If it's below 15°C it reads above 500 until it reaches 25°C, if it's below -20°C it reads 7465°C. I just ignore it because the truck is reading it correctly.

 

the battery was recently changed and the ground wire connecting to the battery was cut to remove dead wire should I replace the ground wire in itself. I am using my box tool to read the temperature yes do you know if the trans thermostat is inside or outside of the transmission I am not going through engine coolant or water in the radiator I think my radiator was like brown water but it doesn’t appear to be leaking

 

I should have looked into the codes more first. Those both appear to relate to bad wiring, or module failure. Look in the stickies for the factory service manual (fsm) and check out 9-617 for p1603 and 8E-44 for u0101. They have a basic troubleshooting for both of those. It's possible the pvc insulation has become a snack for a rodent, or the connector/wire is loose or damaged and could be causing the issues. I have no idea where the thermostat would be on the transmission.

Brown is definitely the wrong color for coolant. That should be replaced. The transmission cooler is built into the same radiator and is known to have issues leaking fluid into the transmission. It won't hurt to check your transmission fluid level, and for any signs of coolant leaking in.

After removing and inspecting the wire harness connectors, disconnect the battery for at least fifteen minutes to restet any codes. Otherwise they will reset after 3 good trips.

 

I do know for a fact, mice had gotten into the engine compartment for sure. I have not been able to find any wiring that was eaten. There is signs of the plastic. That goes around the wire being eaten as well as the firewall being the coolant is not brown, the water is transmission Fluid has recently been flushed. I am talking about the water for the radiator is brown where in the truck should I specifically look for the mice or rats eating? I am not sure which one had gotten and I do know we have both on my property. And what do you mean by 9-617? What exactly is that that I am checking in the manual? Is that pages or something?

 

Rodents like to chew on pvc as the crawl along it, so it could be anywhere. Check around the passenger side firewall behind the air filter box. That is where the pcm is located. That wiring harness goes behind the engine then down to the transmission. The connector on the transmission will be driver side right behind the y-pipe. Any place you see chewed insulation is a place they could have gotten to the wire. Once the wire is exposed it can start corrosion and eventually break connection entirely. I've had to fix more than a few wires that started with a small knife cut in the insulation and turned into a green crumbling mess in a few years time.