What it means
A receiving module detected implausible data from drive motor control module B. Torque, speed or current values fail plausibility checks and are rejected.
How it works
Drive motor control module B manages a traction drive motor and reports values such as torque, speed, or current to other modules. U0593 sets when a receiving module finds data from module B implausible and rejects it, potentially affecting propulsion control.
Common causes
Most likely first.
- Module internal fault or sensor input drift
- Software version mismatch after replacement
- Gateway module routing CAN messages incorrectly
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Scan all modules and save freeze-frame, hybrid or EV, and communication codes before clearing anything, noting which module reported U0593.
- Check the vehicle’s low-voltage battery and charging system for supply problems that could disrupt control-module data.
- Inspect module B’s accessible connectors and harness for damage, moisture, looseness, or evidence of recent repair; do not open high-voltage components.
- Use a suitable scan tool to compare module B’s motor speed, torque, or current data with related vehicle readings and operating conditions.
- Check for gateway or network communication faults and test the applicable low-voltage power, ground, and data circuits to the manufacturer’s specification.
- If a drive motor or control module was recently replaced or updated, verify compatibility, configuration, and software before concluding the module has failed.
Common fixes
- Repair loose, damaged, or corroded low-voltage wiring or connectors serving drive motor control module B.
- Correct a low-voltage battery or charging-system problem affecting module communications.
- Apply the correct configuration or software update if a compatibility mismatch is confirmed.
- Repair a network gateway or communication fault that is corrupting or misrouting module B data.
- Replace drive motor control module B only after circuit and software checks confirm an internal fault.
Can I keep driving?
If the vehicle shows a propulsion, hybrid, or high-voltage warning, limits power, or behaves unpredictably, stop in a safe place and follow the vehicle’s instructions; do not handle high-voltage components. If it appears to drive normally, keep trips short and avoid fast roads or hard acceleration until the fault is diagnosed.
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.