Engine Error
U0100
Lost Communication With ECM/PCM A
Severity
High
Symptoms
Engine dies while driving, cranks but won't start, gauges drop to zero
Common Causes
- Failed PCM relay or blown fuse
- Corroded ground to PCM
- Broken CAN bus wire
- Dead PCM
How to Fix
- 1 Check PCM power and ground circuits
- 2 Replace PCM relay/fuses
- 3 Perform CAN bus continuity test
- 4 Replace and program new PCM
Estimated Repair Cost
USD
$20
–
$1200
Relay/Fuse: $20; PCM Replacement/Programming: $600 - $1,200