ROD 3D8335 - Caterpillar

Table 1
Diagnostic Trouble Codes
J1939 Code CDL Code Code Description Comments
- 3467-5 Main Power Relay : Current Below Normal The Electronic Control Module (ECM) detects a low current condition (open circuit) in the ECM power relay control circuit.
- 3467-6 Main Power Relay : Current Above Normal The Electronic Control Module (ECM) detects a high current condition (short circuit) in the ECM power relay control circuit.
Follow the troubleshooting procedure in order to identify the root cause of the fault.
Illustration 1 g03669690
Schematic diagram for the ECM power relay
Not all connectors are shown. Refer to the Electrical Schematic for the application.
Illustration 2 g03669695
Pin location on the P1 connector for the ECM power relay circuit
(58) ECM power relay control
Table 2
Troubleshooting Test Steps Values Results
1. Inspect Electrical Connectors and Wiring
A. Check that the fuses are not blown.
B. Inspect the terminals on the ECM power relay. Refer to Troubleshooting, "Electrical Connector - Inspect" for details.
C. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the ECM power relay.
D. Check the screw for the ECM connector for the correct torque of 5 N m (44 lb in).
E. Check the harness for abrasion and pinch points from the ECM power relay back to the ECM.
Loose connection or damaged wire
Result: There is a fault in a connector or the wiring.
Repair: Repair any faulty connectors or replace the wiring harness. Ensure that all of the seals are properly in place and ensure that the connectors are correctly coupled.
Replace any blown fuses.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
Result: All connectors, pins, and sockets are correctly coupled and/or inserted. The harness is free of corrosion, abrasion, and pinch points. The fuses are not blown.
Proceed to Test Step 2.
2. Check for Active Diagnostic Codes
A. Connect the electronic service tool to the diagnostic connector.
B. Turn the keyswitch to the ON position.
Note: Do not start the engine.
C. Use the electronic service tool to check for active diagnostic codes.
Diagnostic codes
Result: Diagnostic code 3467-5 is active or recently logged.
Proceed to Test Step 3.
Result: Diagnostic code 3467-6 is active or recently logged.
Proceed to Test Step 6.
3. Check the Battery Supply Voltage at the Relay Connector
A. Turn the keyswitch to the OFF position.
B. Remove the ECM power relay.
C. Turn the keyswitch to the ON position. Do not start the engine.
D. Use a suitable multimeter to measure the voltage between terminal 2 on the harness connector for the relay and a suitable ground.
At least 22 VDC
Result: The voltage is not within the expected range.
Repair: Check the fuse for the ECM power relay.
If the fuse is OK, repair or replace the battery supply wiring to the ECM power relay.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
Result: The voltage is within the expected range.
Proceed to Test Step 4.
4. Create a Short Circuit at the Relay Connector
A. Turn the keyswitch to the OFF position.
B. Remove the ECM power relay.
C.