2021 Peterbilt with a CM2450 with error code 1696

[Luckyjayb]

Working on a dump truck that had a bad demandate in it and had it fixed by one of the members on here. Before and after the fix, I was getting error code 1696, supply signal 5 low voltage or short to ground. The previous guy that put on the horrendous demandate, cut the wires at the ecm plug and throttle pedal and ran wires that was. Nothing ohm’d out right so I had to put a new oem harness from the ecm to firewall and other connections. I tried to make the original connection at the connector for the throttle by soldering and heatshrink. It worked fine for a few days then went back to acting up. While looking at live data on insite, it shows a constant 5 volts. When looking at it on Calterm 3, it will drop down to .2 to .3 bolts when it looses pedal. I’ve disconnected, one at a time, all connectors in signal supply 5 and the pedal is the only issue. It will idle up all day long, but as soon as it is in gear, it’s an Allison automatic 4500 RDS transmission, it starts to act up. The voltage and ohm’d check out fine at idle and with the truck off. Truck only has 80k on the odometer. I’m at a loss on it and I know I’ve got at least 30 hours in electrical troubleshooting on this issue. Anybody have any ideas or suggestions on the next step. Trying to save the customer a harness behind the dash. The last time it went out on the driver, he hit a deep pothole at a slow speed. Thanks in advance