0332619 JOHNSON PLATE, Applique, rear, 25

Illustration 1 g03274357
Table 2
Troubleshooting Test Steps Values Results
1. Determine the Code
A. Establish communication between Cat ET and the Electronic Control Module (ECM). Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the "Warranty Report" from the Aftertreatment ECM before performing any troubleshooting or clearing any diagnostic trouble codes.
C. Determine the diagnostic trouble code that is active.
Diagnostic trouble code
Result: A 5966-5 code is active.
Proceed to Test Step 2.
Result: A 5966-6 code is active.
Proceed to Test Step 3.
Result: A 6309-6 code is active.
Proceed to Test Step 4.
2. Check the Wiring for an Open Circuit
A. Turn the keyswitch to the OFF position for 2 minutes. The keyswitch must be off for two minutes to allow the DEF pump to purge, to reset the code, and to reset the DCU.
B. Disconnect the 12 pin PETU harness connector. Verify that the harness connector is free of debris, corrosion and securely connected.
C. Install a jumper wire between pin 5 on the 12 pin connector on the A5:E2 aftertreatment controller side and a known good ground.
D. Turn the keyswitch to the ON position.
E. Check for an active code.
Diagnostic trouble code
Result: A 5966-5 and a 1235-9 code are both active at the same time.
An open circuit has been detected between the 12 pin PETU harness connector and the DCU harness 53 pin connector.
Replace the PETU wiring harness.
Verify that the problem is resolved. Return the unit to service.
Result: A 1235-9 code is active.
An open circuit has been detected between the A5:E2 Aftertreatment Controller and the 12 pin PETU harness connector.
Repair or replace the wiring harness.
Verify that the problem is resolved. Return the unit to service.
3. Check the DCU Wiring for a Short Circuit
A. Turn the keyswitch to the OFF position for 2 minutes. The keyswitch must be off for two minutes to allow the DEF pump to purge, to reset the code, and to reset the DCU.
B. Disconnect the 12 pin PETU harness connector. Verify that the harness connector is free of debris, corrosion and securely connected.
C. Turn the keyswitch to the ON position.
D. Check for an active code.
Diagnostic trouble code
Result: A 5966-6 and a 1235-9 code are both active at the same time.
A short circuit has been detected between the A5:E2 Aftertreatment Controller and the 12 pin PETU harness connector.
Repair or replace the wiring harness.
Verify that the problem is resolved. Return the unit to service.
Result: A 1235-9 code is active.
A short circuit has been detected between the 12 pin PETU harness connector and the DCU harness 53 pin connector.
Repair or replace the PETU wiring harness.
Verify that the problem is resolved. Return the unit to service.
4. Check the DCU Keyswitch Wiring for a Short Circuit to Ground
A. Turn the keyswitch to the OFF position for 2 minutes. The keyswitch must be off for two minutes to allow the DEF pump to purge, to reset the code, and to reset the DCU.
B. Disconnect the 12 pin PETU harness connector. Verify that the harness connector is free of debris, and corrosion.
C. Disconnect the J1 connector on the A5:E2 aftertreatment controller. Measure the resistance between pin 29 and a known good ground.
Short circuit
Result: There was less than 100k ohms of resistance between pin 29 and ground.
A short circuit has been detected between pin 29 and ground.
Repair or replace the wiring harness.
Verify that the problem is resolved. Return the unit to service.
Result: There was more than 100k ohms of resistance between pin 29 and ground.
Proceed to Test Step 5.
5. Check the DCU Keyswitch Wiring for a Pin to Pin Short Circuit
A. Turn the keyswitch to the OFF position for 2 minutes. The keyswitch must be off for two minutes to allow the DEF pump to purge, to reset the code, and to reset the DCU.
B. Disconnect the 12 pin PETU harness connector. Verify that the harness connector is free of debris, and corrosion.
C. Disconnect the J1 connector on the A5:E2 aftertreatment controller. Measure the resistance between pin 29 and all other pins in the 70 pin connector.
Note: There should be continuity between pins 10 and 29 only.
Short circuit
Result: There was less than 100k ohms of resistance between pin 29 and any other pin in the J1 connector except pin 10.
A short circuit has been detected.
Repair or replace the wiring harness.
Verify that the problem is resolved. Return the unit to service.
Result: There was more than 100k ohms of resistance between pin 29 and all other pins in the J1 connector except pin 10.
Inspect the wiring for an intermittent short.
Repair or replace the wiring harness.
Verify that the problem is resolved. Return the unit to service.
Complete the procedure in the order in which the steps are listed.