Lost Communication With Traction Motor Control Module
What does U0144 mean?
The U0144 code means the vehicle's onboard diagnostic system has detected: Lost Communication With Traction Motor Control Module. This is a critical severity code.
Common Symptoms
- Hybrid or electric vehicle drive system disabled
- Multiple warning lights on dashboard
- Vehicle may not move under electric power
- Reduced power or turtle mode indicator
- High voltage system warning
Probable Causes (Ranked by Likelihood)
- Failed traction motor control module (inverter) Very High
- Damaged CAN bus wiring to traction motor module High
- High voltage interlock tripped Moderate
- Traction motor temperature sensor failure Moderate
- 12V auxiliary battery too low to communicate Low
Step-by-Step Diagnostic Procedure
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Scan for DTCs in all hybrid/EV powertrain modules
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Check 12V auxiliary battery voltage -- low voltage can prevent module communication
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Inspect high-voltage interlock circuit for tripped connections
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Check CAN bus wiring and connectors at the traction motor module
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Verify cooling system for the traction motor is functioning
Frequently Asked Questions
Can I drive with code U0144?
No. This code means the hybrid or electric drive motor control has lost communication. The vehicle may not be able to move under electric power and should be towed to a qualified EV technician.
What causes U0144?
A failed inverter or traction motor controller is the most common cause. Low 12V battery, high-voltage interlock issues, and cooling system problems can also trigger this code.
Is U0144 expensive to fix?
Costs vary widely. A 12V battery replacement may solve it for under $300. Inverter or traction motor controller replacement can cost $1000 to $3000 or more.