Hybrid/EV Battery System Verification

Diagnostic Instructions

Circuit/System Description

Hybrid/EV Battery System Verification

After major internal A4 Hybrid/EV Battery Pack repairs the technician may use the EL-50332 Hybrid/EV Battery Service Tool to verify proper cell group voltage and temperature connection/operation prior to installing the battery pack cover and/or installing the battery pack into the vehicle.

The EL-50332 Hybrid/EV Battery Service Tool communicates with the battery energy control module through the A4 Hybrid/EV Battery Pack low voltage connectors. The tool displays battery cell group voltages for the 96 battery cell groups along with the calculated voltage difference between the highest and lowest readings. The tool also displays the temperatures read by the thermistors located within the battery sections.

Diagnostic Aids

Hybrid/EV Battery System Verification requires that the battery pack is removed from the vehicle and that the battery energy control module contains software. If you are installing a service replacement battery energy control module, connect the battery pack to the vehicle with the EL-50211 Low Voltage Jumper Harness Extension and program the battery energy control module prior to performing Hybrid/EV Battery System Verification. Perform the Clear Secured High Voltage DTCs procedure after successfully programming the service replacement battery energy control module.

Reference Information

Schematic Reference

Hybrid/EV Energy Storage Schematics

Connector End View Reference

Testing for Intermittent Conditions and Poor Connections

Description and Operation

Drive Motor Battery System Description

Electrical Information ReferenceDTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools
  • EL-50211 Low Voltage Jumper Harness Extension
  • EL-50332 Hybrid/EV Battery Service Tool
  • EL-50332-10 220V Power Cable - China
  • EL-50332-125 Vehicle Interface Module Low Voltage 24-Pin Cable
  • EL-50332-135 Hybrid/EV Battery Contactor Assembly Interface Cable
  • EL-50332-175 120 V Power Cable
  • EL-50332-175 120 V Power Cable – EU
  • EL-50332-180 250 V Power Cable – AUS
  • EL-50332-270 Vehicle Interface Module 2

For equivalent regional tools, refer to Special Tools

Circuit/System Testing

Danger: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.

The High Voltage Disabling procedure includes the following steps:

  • Identify how to disable high voltage.
  • Identify how to test for the presence of high voltage.
  • Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.

Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:

  • Safety glasses with appropriate side shields when within 15 meters (50 feet) of the vehicle, either indoors or outdoors.
  • Certified and up-to-date Class "0" Insulation gloves rated at 1000V with leather protectors.
    • Visually and functionally inspect the gloves before use.
    • Wear the Insulation gloves with leather protectors at all times when working with the high voltage battery assembly, whether the system is energized or not.

Failure to follow the procedures may result in serious injury or death.

Danger: High voltage circuits should only be tested using a digital multimeter (DMM) and test leads with at least a CAT III rating, such as the J 39200-A Digital Multimeter. Failure to follow the procedures may result in serious injury or death.

Danger: This vehicle is equipped with a high voltage battery that is completely isolated from the chassis ground. Never utilize AC powered test equipment to probe the high voltage system. Serious injury, death and component damage could occur if the high voltage system is grounded through the electric utility.

Failure to follow the procedure exactly as written may result in serious injury or death.

Danger: Damage to a Lithium Ion hybrid/EV battery pack could result in fire, loss of electrical isolation or exposure to high voltage. Until the high voltage system inspection has been completed, store the vehicle with hybrid/EV battery pack installed outside in a secure area away from buildings and other vehicles and protected from rain, snow and other moisture. Remove the hybrid/EV battery pack high voltage manual disconnect lever and store it in a secure place outside the vehicle. Cover the exposed high voltage opening with UL® listed, or equivalent, insulation tape rated at a minimum of 600 V.

Failure to follow these precautions could result in personal injury, death and property damage.

    Note: Before performing the Hybrid/EV Battery System Verification, make sure all of the external EL-50332 components are in good condition and working order.

  1. Connect the EL-50332-125 to the EL-50332-270 .
  2. Connect the EL-50332-125 to the EL-50332 .
  3. Connect the appropriate regional power cord to the EL-50332 .
  4. Connect the power cord into a known good power outlet.
  5. Turn ON the EL-50332 using the power switch.
  6. At the MAIN MENU, select PACK INFO, press the SELECT soft key.

    7. Note: Selecting One-shot will take and display a single snapshot of the battery parameters, selecting Continuous will display live parameter values.

  7. At the PACK INFO TYPE menu, select ONE-SHOT, press the NEXT soft key.
  8. At the MANUFACTURER menu, select correct BRAND, press the NEXT soft key.
  9. At the MODEL menu, select correct MODEL, press the NEXT soft key.
  10. At the COMM CONNECTION menu, select HYBRID BATTERY CONTACTOR ASSEMBLY, press the NEXT soft key.
  11. Connect the EL-50332-135 to the A4 Hybrid/EV Battery Pack.
  12. Connect the EL-50332-135 to the EL-50332-270 , press the NEXT soft key.
  13. At the PACK INFO menu, scroll down to the DELTA VCELL parameter. Record and verify the DELTA VCELL is less than 0.1 V.
    • If the DELTA VCELL is 0.1 V or greater

      There is an internal battery pack concern. Inspect for conditions such as improper internal wiring connections or improper cell balancing service procedures.

    • The DELTA VCELL is less than 0.1 V
  14. Record and verify all of the battery temperature sensor readings are within 6° C (10.8° F) of each other.
    • If any of the battery temperature sensor readings are 6° C (10.8° F) or greater of each other

      There is an internal battery pack concern. Inspect for conditions such as improper internal wiring connections or damaged components.

    • The battery temperature sensor readings are within 6° C (10.8° F) of each other
  15. All OK.