Applicable Systems
PC200 Excavator
Symptoms
Engine stalls unexpectedly; engine controller loses power; machine shuts down without warning.
Possible Causes
- Engine ECM power supply relay failure
- Main fuse blown for engine controller
- ECM power supply wire short to ground
Troubleshooting Steps
- Step 1: Check engine controller main fuse (30A)
Fuse intact, not blown - Step 2: Test engine ECM power relay operation
Relay coil energizes, contacts close - Step 3: Measure voltage at ECM power terminal
+12V present at ECM with key ON - Step 4: Trace ECM power supply wire for shorts
Wire continuity good, no shorts to ground - Step 5: Replace power relay if faulty
New relay provides stable power to ECM
How to Reset
Clear via monitor panel after ECM power restored.
Common Replacement Parts
- Engine Controller Relay P/N: 600-66-11110
- 30A Main Fuse
Frequently Asked Questions
- Q: What is Komatsu E-code tier system?
E01 = Caution, E02 = Warning, E03 = Machine must be withdrawn from service immediately. Always check tier before continued operation.
Source: truckmanualshub.com Komatsu PDF
Category: Heavy Equipment