C7 and C9 On-Highway Engines Caterpillar

When the "Engine Monitoring Mode" parameter is programmed to "Shutdown", the engine begins a normal shutdown sequence when the following diagnostic codes are activated:

• 100-1 (J1939) Engine Oil Pressure : Low - Most Severe (3)

• 110-16 (J1939) Engine Coolant Temperature : High - Moderate Severity (2)

• 111-1 (J1939) Engine Coolant Level : Low - Most Severe (3)

The engine shutdown will be delayed for 30 seconds if the following conditions occur:

• The "Engine Monitoring Mode" parameter is programmed to "Shutdown".

• The engine shutdown override switch is activated.

Activating the engine shutdown override switch causes the following actions to occur:

• A 1237-31 (J1939) Engine Shutdown Override Switch : Condition Exists code is logged.

• A snapshot is taken.

• The "Check Engine" lamp flashes.

• The "Warning Lamp" is illuminated while the engine shutdown timer is counting down the 30 second delay.

Activating the engine shutdown override switch again will cause the following actions to occur:

• The engine shutdown timer is reset to 30 seconds.

• The 30 second shutdown delay is restarted.

• A 1237-31 (J1939) code is logged.

• An engine snapshot is recorded.

Note: If the "Engine Monitoring Mode" parameter is programmed to "WARNING" or to "DERATE" the engine shutdown override switch is inoperative.

The engine will shut down if the conditions still warrant a shutdown after the 30 second delay.

Perform the following procedure in order to test the circuit for the engine shutdown override switch:

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Illustration 1	g01058271

1. Thoroughly inspect the J1/P1 connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.

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Illustration 2	g01150718
Pin locations on ECM connector (P1-3) Shutdown switch (P1-27) Engine shutdown override switch (P1-55) − Battery

2. Remove terminal 27 from the P1 connector.

3. Connect a jumper wire between terminals P1-27 and P1-65 (-Battery). This will replace the switch circuit with a short circuit.

4. Turn the keyswitch to the ON position.

5. Disconnect one end of the jumper wire and connect the end of the jumper wire. Monitor the warning lamp while the jumper wire is disconnected and connected.

   The warning lamp should illuminate when the jumper wire is connected. The warning lamp should not illuminate when the jumper wire is disconnected.

   If the warning lamp operates correctly, return the wiring to the original configuration. Repair the circuit for the engine shutdown override switch.

   If the warning lamp does not operate correctly, repair the circuit for the warning lamp.