5031557 JOHNSON HOOK, INST PANEL

Illustration 1 g01119909
Schematic
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P1 ECM connector
(P1-43) Engine fan control solenoid
(P1-51) Solenoid return Test Step 1. Inspect Electrical Connectors and Wiring
Turn the keyswitch to the OFF position.
Remove battery power to the ECM.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors for the circuit. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem in the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Check for Active Diagnostic Codes
Restore battery power to the ECM.
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the keyswitch to the ON position.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes. Note: Wait at least 15 seconds in order for the diagnostic codes to become active.
Determine if the problem is related to an open circuit diagnostic code 05 or a short circuit diagnostic code 06. Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active.Repair: The problem may have been related to a faulty connection in the harness. Carefully reinspect the connectors and wiring. Refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - A short circuit diagnostic code (06) is active at this time. Proceed to Test Step 3.
Not OK - An open circuit diagnostic code (05) is active at this time. Proceed to Test Step 4.Test Step 3. Disconnect the Connector for the Fan Control Solenoid in Order to Create an Open Circuit
Turn the keyswitch to the OFF position.
Disconnect the connector for the fan control solenoid.
Turn the keyswitch to the ON position. Wait at least 15 seconds for activation of the diagnostic codes.
Access the "Active Diagnostic Code" screen on Cat ET. Check for an active open circuit diagnostic code (05) for the fan control solenoid.
Turn the keyswitch to the OFF position. Expected Result:An open circuit diagnostic code 05 is now active for the fan control solenoid.Results:
OK - A short circuit diagnostic code (06) was active before disconnecting the connector. An open circuit diagnostic code (05) became active after disconnecting the connector.Repair: Temporarily connect a new fan control solenoid to the harness, but do not install the new fan control solenoid. Verify that there are no active diagnostic codes for the solenoid. If there are no active diagnostic codes for the solenoid, permanently install the new solenoid. Clear any logged diagnostic codes.STOP
Not OK - A short circuit diagnostic code (06) is still active. There is a short circuit between the solenoid harness connector and the ECM. Leave the solenoid connector disconnected. Proceed to Test Step 5.Test Step 4. Create a Short at the Connector for the Fan Control Solenoid
Turn the keyswitch to the OFF position.
Install a jumper wire with Deutsch sockets on each end between terminal 1 (fan control solenoid) and terminal 2 (solenoid return) on P506. Connect the jumper on the harness side of the connector.
Turn the keyswitch to the ON position.
Wait at least 15 seconds for activation of the short circuit diagnostic code 06. Note: Monitor the "Active Diagnostic Codes" screen on Cat ET before installing the jumper wire and after installing the jumper wire.
Remove the jumper wire.
Turn the keyswitch to the OFF position. Expected Result:A short circuit diagnostic code 06 is active when the jumper wire is installed. An open circuit diagnostic code 05 is active when the jumper wire is removed.Results:
OK - The engine harness and the ECM are okay.Repair: Temporarily connect a new fan control solenoid to the harness, but do not install the new fan control solenoid. Verify that there are no active diagnostic codes for the solenoid. If there are no active diagnostic codes for the solenoid, permanently install the new solenoid. Clear any logged diagnostic codes.STOP
Not OK - The open circuit diagnostic code 05 remains active with the jumper in place. The open circuit is between the ECM and the connector for the fan control solenoid. Proceed to Test Step 5.Test Step 5. Check the Operation of the ECM
Disconnect the J1/P1 ECM connector.
Remove the wire for the fan control solenoid from P1-43. Install a jumper wire with Deutsch sockets on each end into P1-43.
Remove the return wire for the fan control solenoid from P1-51. Install a jumper wire with Deutsch sockets on each end into P1-51.
Reconnect the ECM connector.
Turn the keyswitch to the ON position. Monitor the "Active Diagnostic Code" screen on Cat ET. Wait at least 15 seconds for activation of the code. An open circuit diagnostic code (05) should be active for the fan control solenoid.
Check the operation of the ECM by creating a short at the ECM.
Install a wire jumper between the jumper wire for the fan control solenoid and the jumper wire for the solenoid return.
Monitor the "Active Diagnostic Code" screen on Cat ET. Wait at least 15 seconds for activation of the code. A short circuit diagnostic code (06) should be active when the wire jumper is installed.
Remove the wire jumpers. Reconnect all wires and connectors. Expected Result:An open circuit diagnostic code 05 is active when the wire from the fan control solenoid is removed from the ECM connector. A short circuit diagnostic code 06 is active when the wire for the fan control solenoid is connected to the solenoid return.Results:
OK - The ECM is operating properly. The problem is in the wiring between the ECM and the connector for the fan