Cummins ISB4.5 CM2150 Fault Code: 134 PID: 372 SPN: 974 FMI: 4 Remote Accelerator Pedal or Lever Position Sensor 1 Circuit – Voltage Below Normal or Shorted to Low Source.

Circuit Description
The remote accelerator position sensor is a potentiometer attached to the remote accelerator lever. The remote accelerator position sensor varies the signal voltage to the engine control module (ECM) as the remote accelerator lever is depressed and released. Low signal voltage is received by the ECM when the remote accelerator lever is at 0 percent. A high signal voltage is received by the ECM when the remote accelerator is at 100 percent. The remote accelerator pedal position circuit contains a remote accelerator pedal position 5 volt supply, remote accelerator pedal position return, and remote accelerator pedal position signal.

Component Location
The remote accelerator pedal or lever location varies with each original equipment manufacturer (OEM). Refer to the OEM service manual.

Conditions for Setting the Fault Codes
The ECM detects that the remote accelerator pedal signal voltage is less than a calibratible value for more than 1 second.

Action Taken When the Fault Code is Active
-The ECM illuminates the red STOP ENGINE light immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code
-Validate the repair. Start the engine and let it idle for 1 minute.
-The ECM will turn off the red STOP ENGINE light and the fault code will go inactive immediately after the diagnostic runs and passes.
-This fault code can also be cleared with INSITE™ electronic service tool.

Shop Talk
If troubleshooting an intermittent accelerator problem:

The remote accelerator pedal or lever position sensor signal voltage can be monitored with INSITE™ electronic service tool, while flexing the harness to locate the intermittent connection. Intermittent connections will show up as abrupt changes in signal voltage displayed by INSITE™ electronic service tool.

Possible Causes
-Remote accelerator pedal or lever position signal shorted to engine ground or return wires in the OEM harness or sensor
-Failed remote accelerator pedal or lever position sensor
-Open circuit in the remote accelerator signal, supply, or return wire in the harness or connectors.

*The three wires in the remote accelerator position sensor circuit must be twisted together.