What it means
A control module has lost communication with the rear power steering control module. It sets the code when expected messages from that module are not received within the calibrated time.
How it works
The Rear Power Steering Control Module manages or coordinates rear steering assist and reports its status to other controllers over the vehicle network. This code sets when the expected messages from that rear module are not received within the vehicle’s calibrated time, often because of low voltage, a power or ground problem, a damaged connector or network wire, or module failure.
Common causes
Most likely first.
- Power steering module power or ground fault
- Damaged communication wiring
- Loose or corroded connector
- Faulty rear power steering module
- Low system voltage
Symptoms
- Power steering warning
- Heavy or reduced steering assist
- Warning messages
- Other communication codes
How to diagnose it
- Save freeze-frame data and scan all modules for rear-steering, steering, low-voltage, and communication faults; check whether the Rear Power Steering Control Module responds.
- Check battery and charging-system condition, then verify the rear module’s fuses, power feed, and grounds using the vehicle wiring diagram.
- Inspect the rear module connector and accessible communication wiring for corrosion, loose pins, water intrusion, chafing, or damage.
- Use a scan tool to check module communication and gateway status, noting whether other modules also report missing messages from the rear steering system.
- If power and ground are correct, test the communication circuit to the manufacturer’s procedure and specification before replacing the rear module.
Common fixes
- Correct a low battery or charging-system problem affecting module voltage.
- Repair a blown fuse, poor ground, or damaged power feed to the Rear Power Steering Control Module.
- Repair a loose or corroded rear-module connector or damaged communication wiring.
- Correct a verified gateway routing fault.
- Replace the Rear Power Steering Control Module only after its power, ground, and network circuit pass checks.
Can I keep driving?
Rear steering assist may be reduced or unavailable, which can change how the vehicle turns or tracks; drive slowly and avoid abrupt maneuvers. If steering feels unstable or a steering warning indicates loss of control, stop safely and arrange inspection.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.