Important: The Panasonic HV1255 valve regulated lead acid (VRLA) batteries used in the PHT operate at a normal range of approximately 50 percent State Of Charge (SOC). If one or more of the batteries are diagnosed with a low charge or a battery fault and BEFORE battery replacement, the battery pack service charge must be performed. The new replacement battery will be delivered at approximately 80 percent SOC and must be charged alone to 100 percent SOC using the J 42634 battery module charger before installation. Refer to Battery Charging . The starter generator control module (SGCM) functions as a bi-directional converter which converts 12 volts to 42 volts in order to charge the complete battery pack during the battery pack service charge procedure.

The Battery Pack Service Charge Procedure MUST be performed at the pack level if:

Important: If the procedure is interrupted in any way while it is running, the Service Charge Complete Flag will go from 'Incomplete' to 'Done'. In order to restart the service charge procedure, this flag has to go back to 'Incomplete'. The only way to do this is to discharge 1 Ahr out of the battery pack. This could mean driving the vehicle for many miles. So it is very important to make sure that service charge is only started when it has the proper amount of time to complete, and that it does not get interrupted while running.

Battery Pack Service Charge Procedure:

1. Install a scan tool.
2. Turn Service Disconnect in the ON position.
3. Connect a MANUAL battery charger to the underhood battery positive remote jumper stud. Refer to Battery Positive Cable Replacement and to engine ground. Turn ON the battery charger and set to 40-amp setting.
4. Turn ON the ignition.
5. With the scan tool, select the SGCM Service Charge Procedure from Special Functions / SGCM Output Controls, and select ON. This will initiate the battery pack service charge procedure.

Important: The SGCM will continue the charging process and control the battery charging rate with the scan tool disconnected, and the ignition off. Both the ESCM and SGCM are activated and stay awake during the battery pack service charge procedure.

At any time during the battery pack service charge procedure, the scan tool can be reconnected to the vehicle without the ignition being turned ON to verify charging data and status of the battery pack service charge procedure.
A message of "Complete or Incomplete" will be displayed on the scan tool for the battery pack service charge procedure.
If the battery charger is turned off, or disconnected during the battery pack service charge procedure, the battery pack may discharge to an unacceptable SOC. If this event occurs, be certain to terminate the battery pack service charge procedure.
6. Turn OFF the ignition and disconnect the scan tool.

The following conditions will deactivate the battery pack battery pack service charge procedure:

Important: The SGCM monitors the battery pack along with relearning internal memory and will stop the battery pack service charge procedure when 100 percent SOC is met. The battery charger will display a low current output when the process is complete and without battery damage. Base voltage for 100 percent SOC is 12.5 volts +/-0.2 volts. The procedure may take from 30 minutes to 4 hours depending on the battery pack SOC.