The supply voltage from the master Electronic Control Module (ECM) to the sensors for the following parameters is less than the normal level:
- Inlet air temperature
- Engine oil temperature
- Unfiltered engine oil pressure
- Filtered engine oil pressure
- Humidity
A short circuit in the signal wire for the desired speed potentiometer can also generate this code.
System Response:
All of the inputs to the master ECM for the 5 volt sensors assume default values. All other diagnostic codes for the 5 volt sensors are disabled while this diagnostic code is active. The "Status" screen of the Caterpillar Electronic Technician (ET) indicates a "Sensor Supply Fault" for each sensor. This indicates that the sensors are not operating due to an active diagnostic code.
The shutdown output is activated. The code is logged.
Since engine protection is disabled, the engine is shut down.
The condition indicates a possible short circuit to ground or a short circuit between the sensor supply and the return.
Test Step 1. Perform the following test: +5V Sensor Voltage Supply
Results:
- OK - Stop.