Applicable Systems
EMCP 4.2
Symptoms
The Caterpillar Electronic Technician (ET) displays CID 171 with FMI 2: High Speed Travel Switch - Data Erratic, Intermittent, or Incorrect . The specific symptoms depend on the component and severity level. The engine or machine may exhibit reduced performance, warning indicators, or protective shutdown.
Possible Causes
- High Speed Travel Switch sensor or actuator fault - Data Erratic, Intermittent, or Incorrect
- Wiring harness damage, corrosion, or loose connections
- Connector pin corrosion or terminal damage
- ECM internal circuit or processor fault
- Component mechanical failure related to High Speed Travel Switch
Troubleshooting Steps
- Step 1: Connect Caterpillar ET and retrieve active diagnostic codes for CID 171 FMI 2
Diagnostic code details and freeze frame data retrieved - Step 2: Inspect the wiring harness and connectors for the affected component
No visible damage, chafing, or corrosion found - Step 3: Check sensor/actuator power supply, ground, and signal circuits with a multimeter
Values match CAT specifications or discrepancies identified - Step 4: Perform component-specific tests per CAT service manual procedures
Component passes or fails definitive test - Step 5: Clear diagnostic codes and operate machine through normal cycle to verify repair
Code does not return and system operates normally
How to Reset
To reset Caterpillar CID 171 FMI 2: 1) Repair the underlying fault per troubleshooting steps. 2) Use Caterpillar ET to clear the diagnostic code. 3) Cycle the ignition key off for 30 seconds, then on. 4) Operate the machine through normal conditions. 5) If the code returns, contact an authorized CAT dealer for further diagnosis.
Frequently Asked Questions
- Q: What does Caterpillar CID 171 FMI 2 mean?
CID 171 FMI 2 indicates: High Speed Travel Switch - Data Erratic, Intermittent, or Incorrect . This is a Caterpillar diagnostic code related to Drivetrain.
- Q: How do I clear Caterpillar CID 171 FMI 2?
Fix the root cause, then use Caterpillar ET to clear the code. If persistent, contact a CAT dealer.
- Q: Is Caterpillar CID 171 FMI 2 critical?
Severity: Minor. Monitor and service at next opportunity.
Source: Caterpillar Electronic Technician (ET) / CID-FMI Reference Guide
Category: Heavy Equipment