FAN GP 3381413 - Caterpillar

Illustration 1 g03392065
Illustration 2 g03325748
P1 ECM connector
(P1-40) Run/Stop 1
(P1-54) Run/Stop 2
Illustration 3 g03393083
P2 ECM connector
(92) Digital return
Table 2
1. Inspect the Electrical Connectors and Wiring
A. Turn the main disconnect switch to the OFF position.
B. Thoroughly inspect the connectors for the stop switches and the J1/P1 ECM connector.
a. Check for a loose connection or check for poor connections at the connector for the stop switches.
b. Check connections between the stop switches and the ECM.
Refer to Troubleshooting, "Electrical Connectors - Inspect" for information related to inspecting the electrical connectors and wiring.
C. Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit for the stop switches.
D. Check the allen head screw for each of the ECM connectors for the proper torque.
Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
E. Check the harness and wiring for abrasion and for pinch points from the stop switches to the ECM.
Connectors and Wiring
Result: The harness and the wiring appear to be OK.
Proceed to Test Step 2.
Result: There is a problem in the harness connectors and/or the harness.
Repair: Repair the harness connectors or the harness. Ensure that all of the seals for the connectors are properly in place and ensure that the connectors are coupled.
Verify that the repair eliminates the problem.
2. Check the Status of the Switch-on Caterpillar Electronic Technician (ET)
A. Connect Caterpillar Electronic Technician (ET) to the service tool connector.
B. Restore the electrical power to the ECM.
C. Monitor the status of the start/run/stop switch-on Cat ET.
D. Turn the start/run/stop switch to the STOP position.
E. Turn the start/run/stop switch to the START position.
F. Turn the start/run/stop switch to the STOP position.
ECS Status and Active 1656-2 Diagnostic Code
Result: The status for the switch is correct in both the START and STOP positions. A diagnostic code for the switch is not active.
Repair: The switch appears to be operating correctly. There may be an intermittent problem in the harness or in a connector.
For information related to identifying intermittent electrical problems, refer to Troubleshooting, "Electrical Connectors - Inspect".
Result: The parameter for the switch is not correct in either the STOP or the START positions.
Proceed to Test Step 3.
3. Check the Wiring for an Open Circuit
A. Turn the main disconnect switch to the OFF position.
B. Disconnect the J1/P1 and the J2/P2 ECM connectors.
C. Remove the wires from the switch.
D. Install a wire jumper between the wire J842-BK (Black) and the wires R775-OR (Orange) R776-PK (Pink) at the switch.
E. Measure the resistance between P1-40 and P2-92 at the P1 and P2 ECM connectors.
F. Measure the resistance between P1-54 and P2-92 at the P1 and P2ECM connectors.
G. Return all wiring to the original configuration.
Continuity Between P1-40 and P1-54
Result: The measurement indicated a short circuit. The circuit is OK.
Proceed to Test Step 4.
Result: The measurement indicated an open circuit.
Repair: Repair the connectors or wiring and/or replace the connectors or wiring.
Verify that the repair eliminates the problem.
4. Check the Harness Wiring for a Short Circuit
A. Disconnect the J1/P1 and J2/P2 ECM connector.
B. Measure continuity between terminal P1-40