Sensor Supply 4 Circuit – Voltage Below Normal or Shorted to Low Source
|Fault Code: 2186
Sensor Supply 4 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at the +5 volt sensor supply circuit to the accelerator pedal position sensor.
Engine will only die.
ISB, ISC, and ISL with CM2150 – Accelerator Pedal Position Sensor Supply Voltage Circuit
Sensor supply 4 of the electronic control module (ECM) provides a 5 volt supply to the accelerator pedal position sensor. The accelerator position sensor is a hall effect sensor attached to the accelerator pedal. The accelerator position sensor varies the signal voltage to the ECM as the accelerator pedal is depressed and released. Low signal voltage is received by the ECM when the accelerator pedal is at 0 percent. A high signal voltage is received by the ECM when the accelerator pedal is at 100 percent. The accelerator pedal position circuit contains an accelerator pedal position 5 volt supply, accelerator pedal position return, and accelerator pedal position signal.
The accelerator pedal is located in the cab. Refer to the original equipment manufacturer (OEM) troubleshooting and repair manual.
Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position.
Conditions for Setting the Fault Codes
The ECM detects that the sensor supply 4 signal voltage is less than 4.75-VDC for more than 1 second.
Action Taken When the Fault Code is Active
- The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
- The engine will only die.
Conditions for Clearing the Fault Code
The ECM will turn off the amber CHECK ENGINE light immediately after the diagnostic runs and passes.
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If necessary, recalibrate the ECM. Refer to Procedure 019-032 (ECM Calibration Code) in Section 19 in the corresponding Troubleshooting and Repair Manual for the engine being serviced.
Low voltage on the 5 volt supply wire can be caused by a short circuit to ground in the supply wire, a short circuit between the supply wire and return circuit, a failed accelerator, or a failed ECM power supply.