SHAFT-PUMP IDLER 1H7481 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the listed codes. Also use this procedure if a spark is not detected.
Table 1
Diagnostic Trouble Codes for the Ignition System for the Aftertreatment Regeneration Device (ARD)    
J1939 Code    Description    Conditions Which Cause the Code    System Response    
3484-5     Aftertreatment #1 Ignition : Current Below Normal     The current flow through the primary ignition circuit is below the threshold.
Usually, this condition is caused by a problem in an electrical connector.     A snapshot is triggered. The code is logged. If a regeneration is in progress, the ARD completes the regeneration. The ARD is disabled after the regeneration is complete.    
3484-6     Aftertreatment #1 Ignition : Current Above Normal     Two conditions can cause this code. There is excessive current flow through the secondary ignition circuit or there is excessive current flow through the primary ignition circuit.
The following problems can cause excessive current flow:
The spark plug is fouled.
There is a problem with the ignition wire between the ignition coil and the spark plug. These problems usually occur because the ignition wire has been damaged by excessive heat or improper routing.
The ignition coil has a problem.     A snapshot is triggered. The code is logged. If a regeneration is in progress, the ARD completes the regeneration. The ARD is disabled after the regeneration is complete.    
4265-6     Aftertreatment #1 Transformer Secondary Output : Current Above Normal     The ARD has attempted to ignite six times. All of the attempts were unsuccessful. The ECM has detected a problem with the current flow through the secondary circuit. The primary circuit is OK.
The following problems can cause this code:
The spark plug is fouled.
There is a problem with the ignition wire between the ignition coil and the spark plug. These problems usually occur because the ignition wire has been damaged by excessive heat or improper routing.
There is a problem with the ARD head. The ground probe is missing or bent.
The ignition coil has a problem.     The code is logged.    
Follow the troubleshooting procedure in order to identify the root cause of the problem.    Illustration 1 and Illustration 2 show an overview of the troubleshooting procedure. Follow the steps in order.
Illustration 1 g02001376
Illustration 2 g02061455
Components for the Ignition SystemThere are two possible locations for the ignition coil. Refer to Illustration 3 and Illustration 4.