Caterpillar — Test Step 13. Create an Open at the ECM
Testing & diagnosis · Suspect sensor signal wire at ECM connector
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
Before you start
- Disconnecting the Atmospheric Pressure Sensor will cause several sensor diagnostic codes to become active. Troubleshoot the original code.
Procedure
- Turn the ECS to the OFF/RESET position.
- Disconnect the suspect sensor signal wire from the ECM connector.
- Turn the ECS ON, engine OFF.
- Check if the CID-FMI changed from 04 to 03.
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.