Code U0136 indicates that the vehicle's primary communication network has lost contact with the Rear Differential Control Module. This typically occurs in vehicles equipped with electronically controlled limited-slip or locking rear differentials.
Corroded, frayed, or broken wires in the harness leading to the rear differential, often caused by road debris or rodent damage.
Loose, corroded, or improperly seated electrical connectors at the Rear Differential Control Module.
A blown fuse or failed relay preventing the Rear Differential Control Module from powering on.
Internal hardware failure within the Rear Differential Control Module itself.
A short or open circuit in the vehicle's communication network affecting the rear bus branch.
A failure in the main engine computer's communication gateway, though this is rare for this specific code.
Yes, the vehicle is generally drivable, but you will likely experience reduced traction and the loss of electronic differential control features.
No. This is a communication code, meaning the computer cannot talk to the module. It does not necessarily indicate a mechanical failure of the gears or axles.
No. U0136 is almost always caused by wiring, power supply, or the rear module itself. Replacing the PCM is rarely the correct solution and is generally discouraged unless all other network faults are ruled out.