Applicable Systems
PC200 Excavator
Symptoms
Throttle position sensor reading below minimum expected voltage; engine may default to idle or limp mode.
Possible Causes
- Throttle sensor signal wire short to ground
- Sensor wiper contact failure
- Sensor +5V supply interrupted
Troubleshooting Steps
- Step 1: Check throttle sensor +5V supply
+5.0V present at supply pin - Step 2: Check signal wire for short to ground
Resistance > 10k ohm to ground - Step 3: Inspect sensor internal wiper track for wear
Wiper contact intact - Step 4: Replace throttle sensor if signal low
New sensor voltage within spec - Step 5: Clear code and calibrate throttle range
Throttle calibration successful
How to Reset
Clear via service monitor after calibration.
Common Replacement Parts
- Throttle Position Sensor P/N: 621-06-17100
Frequently Asked Questions
- Q: What happens if throttle sensor fails completely?
Engine defaults to safe idle mode (limp home). Machine can move but at reduced speed/power.
Source: truckmanualshub.com Komatsu PDF
Category: Heavy Equipment