BELT-SERPENTINE 2414982 - Caterpillar

Table 1
Diagnostic Trouble Codes    
J1939 Code    CDL Code    Code Description    Comments    
5966-5     3965-5     Aftertreatment 1 Diesel Exhaust Fluid Control Module Power Supply : Current Below Normal     An open circuit has been detected on the keyswitch circuit between the A5:E2 aftertreatment controller and the DCU.    
5966-6     3965-6     Aftertreatment 1 Diesel Exhaust Fluid Control Module Power Supply : Current Above Normal     A short circuit has been detected on the keyswitch circuit between the A5:E2 aftertreatment controller and the DCU.    
6309-6     3966-6     Aftertreatment #1 Diesel Exhaust Fluid Control Module Power Supply #2 : Current Above Normal     Pin 29 of the A5:E2 aftertreatment controller has a short circuit to battery positive or negative.    
Follow the troubleshooting procedure in order to identify the root cause of the problem.    
Illustration 1 g03274357
Complete the procedure in the order in which the steps are listed.
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 3965-5 or 5966-5 code is active.
Proceed to Test Step 2.
Result: A 3965-6 or 5966-6 code is active.
Proceed to Test Step 3.
Result: A 3966-6 or 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