BEARING 7H9566 - Caterpillar

Use this procedure to troubleshoot a problem with a solenoid valve. Also, use this procedure if one of the following diagnostic codes is active or easily repeated.
Table 1
J1939 Code and Description CDL Code and Description Comments
677-5
Engine Starter Motor Relay : Current Below Normal 444-5
Starter Motor Relay : Current Below Normal This code indicates that there is a problem with the engine starter motor relay and/or the electrical circuit on the ECM.
677-6
Engine Starter Motor Relay : Current Above Normal 444-6
Starter Motor Relay : Current Above Normal This code indicates that there is a problem with the engine starter motor relay and/or the electrical circuit on the ECM. Electrical Checkouts on the Cat® Electronic Technician (ET)
Table 2
Component Electrical Checkout
Engine Starter Motor Relay Attempt to start the engine. Once the ECM attempts to energize the solenoid, the code will become active. Refer to the application-specific schematic for the "Engine Starter Motor Relay" wiring circuit.
Table 3
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Determine if a code is active or logged.
Codes
Result: A -5 code is active or logged.
Proceed to Test Step 2.
Result: A -6 code is active or logged.
Proceed to Test Step 3.
2. Check the Wiring for an Open Circuit
A. Verify that the harness connector is free of debris, free of corrosion, and securely connected.
B. Disconnect the relay from the harness.
C. Connect a jumper wire between the terminals of the harness connector for the affected coil. The coil is replaced with a short circuit.
Create a Short
Result: A -5 code became active during the electrical checkout. The Electronic Control Module (ECM) did not detect the jumper wire. There is an open circuit in the wiring between the coil and the ECM connector. There may be a problem with a connector.
Repair: Repair or replace the connectors or the wiring.
Verify that the repair eliminated the problem.
Result: A -6 code is activated during the electrical checkout. The ECM detected the jumper wire. There is a problem with the solenoid.
Repair: Replace the solenoid.
Verify that the repair eliminated the problem.
3. Check the Wiring for a Short Circuit
A. Disconnect the relay from the harness.
Create an Open
Result: A -6 code became active during the electrical checkout. The ECM did not detect the open circuit. There is a short circuit in the wiring between the coil and the ECM connector. There may be a problem with a connector.
Repair: Repair or replace the connectors or the wiring.
Verify that the repair eliminated the problem.
Result: A -5 code is activated during the electrical checkout. The ECM detected the open circuit. There is a problem with the solenoid.
Repair: Replace the solenoid.
Verify that the repair eliminated the problem.
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).