Cummins N14 STC, Celect, Celect Plus – Service Manual Engine Brake Does Not Operate (CELECT™ or CELECT Plus™)

Electronic fault codes active or high counts of inactive fault codes

Refer to Section TF in the for CELECT Plus™ Systems Troubleshooting and Repair Manual, Bulletin 3666130, or Section TF in the for CELECT™ Systems Troubleshooting and Repair Manaul, Bulletin 3666084.

Engine brake piston(s) is stuck

Check the engine brake piston(s) for freedom of movement. Replace the engine brake piston(s) if necessary. Refer to Procedure 020-024 in Section 20.

Engine brake control valve(s) is malfunctioning

Check the engine brake control valve(s). Replace the engine brake control valve(s) if necessary. Refer to Procedure 019-034 and Procedure 019-035 in Section 19 of the CELECT Plus™ Systems Troubleshooting and Repair Manual, Bulletin 3666130, and the CELECT™ Systems Troubleshooting and Repair Manual, Bulletin 3666084.

Engine brake harness connectors are loose or broken

Check the engine brake harness connectors. Check the engine brake harness for continuity. Refer to Procedure 019-136 in Section 19 of the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130.

Clutch switch or circuit is malfunctioning

Check the clutch switch adjustment, switch, and circuit. Refer to Procedure 019-009 and Procedure 019-010 in Section 19 of the CELECT Plus™ Systems Troubleshooting and Repair Manual, Bulletin 3666130, and the CELECT™ Systems Troubleshooting and Repair Manual, Bulletin 3666084.

Throttle position sensor is misadjusted or malfunctioning

Check throttle position sensor for proper adjustment and operation. Refer to Procedure 019-085 and Procedure 019-086 in Section 19 of the CELECT Plus™ Systems Troubleshooting and Repair Manual, Bulletin 3666130, or Procedure 019-085 and Procedure 019-086 in Section 19 of the CELECT™ Systems Troubleshooting and Repair Manual, Bulletin 3666084.

Service brake pressure switch or circuit is malfunctioning

Check the service brake pressure switch and circuit. Refer to the OEM service manual.

Engine brake enable circuit is malfunctioning

Check the engine brake enable circuit. Refer to Procedure 019-035 in Section 19 of the CELECT™ Plus Systems Troubleshooting and Repair Manual, Bulletin 3666130, or the CELECT™ Systems Troubleshooting and Repair Manual, Bulletin 3666084.

Engine electrical ground is malfunctioning

Check engine ground to chassis and chassis ground to battery negative (-) post. Refer to the OEM service manual.

Solenoid valve is malfunctioning

Check for voltage at the solenoid valve. Refer to Procedure 020-024 in Section 20.

Solenoid valve filter screen is covered with debris

Remove the solenoid valve and clean or replace the screen. Refer to Procedure 020-024 in Section 20.

Lubricating oil leak (internal)

Check the engine brake hose connections, the engine brake housing, and the jumper tube o-rings for oil leaks. Refer to Procedure 020-024 in Section 20.

Engine brake lubricating oil supply line is restricted

Remove the oil supply line. Inspect the supply line for a restriction.

Engine brake adjustment is not correct

Adjust the engine brakes. Refer to Procedure 020-024 in Section 20.