C175 Oil&Gas Offshore Engine Caterpillar

Circuit Breaker - Test

Usage:

Use this procedure to troubleshoot a problem with the Diesel Exhaust Fluid (DEF) control module circuit breaker. Also, use this procedure if one of the following diagnostic codes is active or easily repeated.

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Table 1
J1939 Code and Description	CDL Codes and Description	Comments
7417-5 Aftertreatment #1 DEF Control Module Circuit Breaker : Current Below Normal	4700–5 Aftertreatment #1 DEF Control Module Circuit Breaker : Current Below Normal	The AC circuit breaker on the Diesel Exhaust Fluid (DEF) dosing cabinet has an open circuit.
7417-6 Aftertreatment #1 DEF Control Module Circuit Breaker : Current Above Normal	4700–6 Aftertreatment #1 DEF Control Module Circuit Breaker : Current Above Normal	The AC circuit breaker on the DEF dosing cabinet has a short circuit.

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Table 2
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. Turn the AC and DC breakers to the OFF position. B. Disconnect the wiring from the AC circuit breaker connector. C. Disconnect the J1 and J2 wiring harnesses from the Selective Catalyst Reduction (SCR) controller. D. Measure the resistance between the following pins on each connector: - Pin 11 (AC circuit breaker) and Pin J2-92 (SCR controller) - Pin 12 (AC circuit breaker) and Pin J1-46 (SCR controller) - Pin 14 (AC circuit breaker) and Pin J1-47 (SCR controller)	Open Circuit	Result: There were less than 10 ohms of resistance on each of the wires. Repair: A failed AC circuit breaker has been detected. Replace the AC circuit breaker. Verify that the repair eliminated the problem. Return to service. Result: There were more than 10 ohms of resistance on one or more of the wires and a known good ground. Repair: An open circuit has been detected. Repair or replace the wiring harness. Verify that the repair eliminated the problem. Return to service.
3. Check the Wiring Harness for a Short Circuit to Ground A. Turn the AC and DC breakers to the OFF position. B. Disconnect the wiring from the AC circuit breaker connector. C. Disconnect the J2 wiring harnesses from the SCR controller. D. Measure the resistance between the following pins on AC circuit breaker and a known good ground: - Pin 12 (AC circuit breaker) and Ground - Pin 14 (AC circuit breaker) and Ground	Short Circuit	Result: There were more than 100 K ohms of resistance on each wire and a known good ground. Proceed to Test Step 4. Result: There were less than 100 K ohms of resistance on one or more wires and a known good ground. Repair: A short circuit to ground has been detected. Repair or replace the wiring harness. Verify that the repair eliminated the problem. Return to service.
4. Check the Wiring Harness for a Pin to Pin Short Circuit A. Turn the AC and DC breakers to the OFF position. B. Disconnect the wiring from the AC circuit breaker connector. C. Disconnect the J2 wiring harnesses from the SCR controller. D. Measure the resistance between the following pins on AC circuit breaker and all other pins in the SCR controller connector: - Pin J1-46 (SCR controller) and All other J1 Pins (SCR controller connector) - Pin J1-47 (SCR controller) and All other J1 Pins (SCR controller connector)	Short Circuit	Result: There are more than 100 K ohms of resistance on each wire and all other pins in the SCR controller J1 connector. Repair: A failed AC circuit breaker has been detected. Replace the AC circuit breaker. Verify that the repair eliminated the problem. Return to service. Result: There are more than 100 K ohms of resistance on one or more of the wires and all other pins in the SCR controller J1 connector. Repair: A short circuit to ground has been detected. Repair or replace the wiring harness. Verify that the repair eliminated the problem. Return to service.

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).