Symptom Tree
Electronic fault codes are active |
For instructions on how to read active fault codes, refer to Procedure 101-007 (Electronic Controlled Fuel System) in Section 1. If fault codes are active, contact a Cummins Authorized Repair Facility. |
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Engine brake harness connectors are loose or broken |
Check the engine brake harness connectors. |
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Engine brake on/off switch is off |
Turn on the switch. |
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Engine electrical ground is malfunctioning |
Check engine ground to chassis and chassis ground to battery negative (-) post. Refer to the OEM service manual. |
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Engine brake switch wires or connectors are loose |
Check the engine brake on/off switch, selector switch, clutch switch, and throttle switch for loose wires and connections. |
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Lubricating oil leak (internal) |
Check the engine brake hose connections, the engine brake housing, and the jumper tube o-rings for oil leaks. the OEM service manual |
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Engine brake lubricating oil supply line is restricted |
Remove the oil supply line. Inspect the supply line for a restriction. |
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Engine brake adjustment is not correct |
Adjust the engine brakes. Refer to a Cummins Authorized Repair Location. |
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Contact a Cummins Authorized Repair Facility |