Cummins ISX12 CM2250 (2010-12) Fault Code: 4293 PID: SPN: 5097 FMI: 3 Engine Brake Active Lamp- Voltage Above Normal or Shorted to High Source

Circuit Description
The engine brake active lamp relay is controlled by the engine control module (ECM). It is energized during engine braking to illuminate the brake lamps at the rear of the vehicle.

Component Location
Location of the relay is OEM dependent. Refer to the OEM service manual for the relay location.

Conditions for Running the Diagnostics
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes
The ECM detects that the engine brake lamp active relay signal circuit has gone above 4.75-VDC for more than 1 second.

Action Taken When the Fault Code is Active
The ECM illuminates the amber CHECK ENGINE lamp and/or the malfunction indicator lamp (MIL) immediately when the diagnostic runs and fails.
Conditions for Clearing the Fault Code
To validate the repair, start the engine and let it idle for 1 minute.
The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.
For On-Board Diagnostics (OBD) engines, the ECM will turn off the MIL after three consecutive trips where the diagnostic runs and passes.
The ?Reset All Faults? command in INSITE? electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk
The ECM monitors the voltage level on the engine brake lamp active relay circuit. If the voltage goes above a calibratable limit, this fault is recorded.

Possible causes of this fault code include:

? An open signal circuit in the OEM harness.

? An open return circuit in the OEM harness.

? A pin-to-pin short circuit in the OEM harness.

Possible Cause:
1) Engine Brake lamp relay failure
2) OEM harness
3) ECM calibration