Caterpillar — Test Step 15. Check for Shorts in the Wiring Harness
Testing & diagnosis · Suspect sensor wiring harness
From a Caterpillar service manual covering: 3500B Engine, PM3516, PM3516 Power Module. Check it applies to your exact model before use.
Applies to: Caterpillar 3500B engine
Procedure
- Turn the ECS to the OFF/RESET position.
- Disconnect ECM connector J1/P1, ECM connector J2/P2 and the suspect sensor.
- Measure resistance between signal wire and supply voltage at the ECM connector.
- Measure resistance between signal wire and sensor return line.
- Measure resistance between signal wire and engine ground.
- Reconnect all connectors.
Specs & values
- Resistance should be greater than 20,000 Ohms
Source: Caterpillar service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.