2000 cummins ats stage 2 trans won't shift out of first. Edge cts reads it being in second but doesn't shift out of first. p0112 (intake air temp sensor 1 circuit voltage low) and  p1693 (fault in companion module) codes are present. What causes this shifting issue and how can I fix it? 

4 minutes ago, 2000cummins said:

2000 cummins ats stage 2 trans won't shift out of first. Edge cts reads it being in second but doesn't shift out of first. p0112 (intake air temp sensor 1 circuit voltage low) and  p1693 (fault in companion module) codes are present. What causes this shifting issue and how can I fix it? 

A lot of the time the governor pressure solenoid fails, it's supposed to go to 3rd but I've had a few times where it stays in 1st no matter what you do. May wanna start there. Hard to tell you without the vehicle in front of me honestly... another one is the throttle valve could be stuck wide open thinking it's being floored. Make sure the cable from the throttle to the trans is working and that there is a return spring for it on the trans. If it snaps which is common then the TV will stay wide open. Make sure the cable isn't frayed and hanging up. Start there, if that's not it get a scan tool and look at the gov pressure data or throw a solenoid and sensor in. There cheap assurance. Beyond that it's all valve body. 

 

If you rev the truck out to redline and let off will it upshift at all? If the 2nd gear band/strut/anchor broke or bent it'll seem like your stuck in first but if you rev it out real far then let off it'll jump to 3rd. 

The two codes mentioned in the first question do not clear, however when I re ran the codes I got a high battery voltage (jump started it after bleeding the injector lines a couple days ago) and ,with the two codes that don't clear another p1693 code showed with them. I cleared the second p1693 and voltage codes and the truck drives and shifts fine now. Is there an underlying issue that would cause that? The two original codes have been on since I bought the truck but as soon as the high voltage and second p1693 code came on it wouldn't shift. I only started the truck and let it run for about 5 minutes then drove it and as soon as I realized it wasn't shifting I pulled back into the drive way and cleared the two new codes and it shifted fine. Sorry if I'm being confusing I'm not a diesel mechanic by any means

P1693 is just indicating an issue in another module. These trucks use the ECM as the main module so it's saying the VP44 or PCM computer has a problem. Being the truck runs it's not the VP. So PCM is the problematic part. The voltage is interesting, so the PCM controls charging as well as the trans and some body control functions like cruise control, AC request, interior light etc. it's before full CAN became the standard where everything is full computer control. So your Edge your using only communicates with the ECM. You need to get a scan tool to access the PCM to find the main issue. BUT for now, check wiring, check the plugs on the PCM. Look in the relay/fuse box under the hood, make sure everything is good there. One relay is labeled "transmission" swap it with an identical relay near it that isn't a major component. So like AC or something irrelevant. If the problem goes away a relay is probably the issue. If it exists still you may want to either check alternator function itself that it's not dead shorting the PCM, if you can find a friend and borrow a PCM to test that works too. Essentially your gonna diag without the codes. Honestly on these trucks codes mean very little. I almost never put a scan tool on them, the computer never tells you what's really wrong and generally even on brand new vehicles the code doesn't mean that's the issue.

 

 

example: had a 97 7.3 Ford F-350, torque converter unlocks at cruise condition and if you accelerate at all it locks up then unlocks again. No codes, no other issue. 7 shops took a crack at it. Even put a whole transmission, PCM and wiring to the trans. 15 minutes after I got it here I found that the multifunction wire on the brake pedal switch wasn't switching to function 2. Function 2 is determined by the PCM using the resistance of the brake lights lighting up to swap to secondary function. Brake light bulbs were burnt out causing the pcm to stay in function 1 on that wire which then caused the lockup problem. After all that a set of bulbs fixed what 7 other shops and $5000 couldn't figure out. So take that how you will but just because there is a code doesn't mean that's what's up. The IAT sensor thing can be the sensor, plug, plus water proofing sleeve or the wire itself. You should fix that though, IAT helps to determine fueling and timing control