Battery - Testing/Charging On BEM Equipped Vehicles
27 Battery testing and charging - vehicles with BEM (J644)27 10 03
2023330/1
May 5, 2010
Affected Vehicles
Condition
Battery testing and charging for vehicles equipped with a Battery Energy Manager (BEM - J644).
Technical Background
When the InCharge 940 is used as a battery charger in auto mode, it performs a battery condition test and may prematurely fail the battery if the charging takes place at the jumper posts in the engine compartment. This is due to the added resistance in the system between the battery and jumper posts. When the InCharge 940 is used as a battery charger in manual mode, the battery condition test is not performed.
Production Solution
Not applicable.
Service
TESTING THE BATTERY
VAS scan tool:
Follow Guided Fault Finding battery test plan in service work.
CHARGING THE BATTERY
Midtronics INC-940 diagnostic charging station:
Connect the charging station - auto mode
1. Connect the InCharge 940 positive cable clamp to the positive battery post.
2. Connect the negative cable clamp to the vehicle's negative battery cable downstream at the body attachment point. (Figure 1 illustrates this on an Audi Q7 model).
Tip: This connection ensures J644 remains in the loop to accept battery charge data.
3. Enter the DIN value listed on the battery.
Connect the charging station - manual mode
1. Connect the InCharge 940 to the battery jumping posts in the engine compartment or as described in the auto mode section.
2. Enter the DIN value listed on the battery.
Tip: Please obtain the battery serial number (example: VAO 99050770MX), located on top of the battery, for battery testing or replacement and for future reference or when contacting TAC.
Warranty
This TSB is informational only and not applicable to any Audi warranty.
Additional Information
All parts and service references provided in this TSB are subject to change and/or removal. Always check with your Parts Department and service manuals for the latest information.