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DTC P0AF8

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0AF8: Hybrid System Voltage

Circuit/System Description

The drive motor battery contains 288 cells. Groups of three cells are welded together in parallel. There are a total of 96 cell groups in the drive motor battery assembly. These cell groups are electrically connected in-series. Each individual cell group is rated at 3.7 V, for a nominal system voltage of 355 V direct current. The battery cells are also grouped together into three sections. The first 90 cells/30 cell groups make up battery section one. This section is adjacent to the cowl and contains batteries 67 through to 96. Battery section two is located behind section one. It is made up of 72 cells/24 cell groups and contains batteries 43 through to 66. The transverse battery section is section number three, it is made up of the remaining 126 cells/42 cell groups and contains batteries 1 through to 42. The three battery sections are individually serviceable components.

The battery energy control module monitors the voltage of the 96 battery cell groups through the four drive motor battery high- voltage interface controllers. Voltage sense lines are attached to each individual cell group, and these sense lines terminate at a connector located on the top surface of the battery section. A serviceable voltage sense harness joins this connector to a drive motor battery high-voltage interface control module, also located on the top surface of the battery section. The drive motor battery high-voltage interface control module encodes the voltage reading and transmits it to the battery energy control module through the battery control harness. There is one drive motor battery high-voltage interface control module located on battery sections one and two, and two drive motor battery high-voltage interface control modules associated with battery section three. The drive motor battery high-voltage interface control module, voltage sense harnesses, battery control harness and battery energy control module are all considered serviceable components.

The battery energy control module will determine when a fault condition is present. Diagnostics and system status are communicated from the battery energy control module to hybrid powertrain control module 2 through serial data. The hybrid powertrain control module 2 is the host controller for diagnostic trouble code information.

Conditions for Running the DTC

    • The hybrid/EV battery main contactors are closed.
    • None of the following DTCs are set; P0ABB, P0ABC, P0ABD, P1A07, P1AE8, P1AE9, P1AEA, P1AEB, P1AEC, P1AED, P1AE20 P1AE27 or P1E28.

OR

    • The hybrid/EV battery main contactors are open.
    • The charger contactors are closed.
    • The multi-function contactor is closed.
    • None of the following DTCs are set; P0ABB, P0ABC, P0ABD, P0D4E, P0D4F, P0D5C, P16C5, P1A07, P1EEB, P1EEC or P1ECE.

Conditions for Setting the DTC

    • The difference between the Hybrid/EV Battery pack voltage and the hybrid powertrain control module bus voltage is greater than 12 V.
        OR
    • The difference between the Hybrid/EV Battery pack voltage and the charger module's bus voltage is greater than 12 V.

Action Taken When the DTC Sets

DTC P0AF8 is a type A DTC.

Conditions for Clearing the DTC

    • DTC P0AF8 is a type A DTC.
    • The Clear Secured High-Voltage DTCs reset function must be performed to prevent resetting the DTC.

Diagnostic Aids

An open charger fuse may cause P0AF8 to set.

Reference Information

Schematic Reference

Hybrid Energy Storage Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Drive Motor Battery System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-48900 HEV Safety Kit

For equivalent regional tools, refer to Special Tools .

Circuit/System Verification

  1. Verify that no other DTCs are set.
  2. If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
  3. Clear the P0AF8 and perform the Clear Secured High Voltage DTCs reset function. Refer to Clear Secured High-Voltage DTCs .
  4. Put the vehicle into Charge Mode by plugging in the wall charger.
  5. Observe the hybrid powertrain control module 2 Battery Charger High-Output parameter and the hybrid/EV battery energy control module Hybrid Battery Pack Terminal 1 Voltage parameter. Each reading should be within 12 V of each other and DTC P0AF8 did not reset.
  6. If readings are not within 12 V of each other or the DTC is set, refer to Battery Charger Bus Diagnostics.
    If readings are within 12 V of each other and the DTC is not set, refer to Battery Main Bus Diagnostics.

Circuit/System Testing

Danger: High voltage enabling and disabling shall be only performed by High Voltage Qualified Technicians. The procedures for high-voltage enabling/disabling can be found in the service instructions and must be strictly followed at all times. The usage of the Protocol High Voltage Disabling/Enabling is mandatory. The High-Voltage Qualified Technician is responsible for the adherence to the manufacturer's service instructions as well as current national legal regulations.

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

Questions regarding training can be answered by your national training centre.

Danger: Any hybrid/EV battery pack replacement shall be performed by High-Voltage Qualified Technicians only. The replacement procedure can be found in the service instruction and must be strictly followed at all times. The High-Voltage Qualified Technician is responsible for adherence to the manufacturer's service instructions as well as current national legal regulations. If the hybrid/EV battery pack needs to be replaced contact the Technical Assistance Centre for further instructions prior to removal of the battery pack.

Battery Charger Bus Diagnostics

  1. Ignition OFF, disable the high voltage at the T18 Battery Charger. Refer to High Voltage Disabling .
  2. Disconnect the X7 harness connector at the A28 hybrid/EV battery contactor assembly.
  3. Disconnect the X5 harness connector at the A28 hybrid/EV battery contactor assembly.
  4. Test for infinite resistance between the terminals listed below:
  5. • High-voltage DC (-360 V) negative terminal B X5 harness connector at the A28 hybrid/EV battery contactor assembly to vehicle chassis earth.
    • High-voltage DC (+360 V) positive terminal A X5 harness connector at the A28 hybrid/EV battery contactor assembly to vehicle chassis earth.
    • High-voltage DC (+360 V) positive terminal A X5 harness connector at the A28 hybrid/EV battery contactor assembly and the high-voltage DC (-360 V) negative terminal B X5 harness connector at the A28 hybrid/EV battery contactor assembly.
    If less than the specified value, replace the high-voltage DC cables. After the repair is complete with a scan tool, the Clear Secured High-Voltage DTCs reset function must be performed.
  6. Test for less than 10 Ω between the terminals listed below:
  7. • High-voltage DC (-360 V) negative terminal B X4 harness connector at the T18 Battery Charger and the high voltage DC (-360 V) negative terminal B X5 harness connector at the A28 hybrid/EV battery contactor assembly.
    • High-voltage DC (+360 V) positive terminal A X4 harness connector at the T18 Battery Charger and the high- voltage DC (+360 V) negative terminal A X5 harness connector at the A28 hybrid/EV battery contactor assembly.
    If greater than the specified value, replace the high-voltage DC cables. After the repair is complete with a scan tool, the Clear Secured High-Voltage DTCs reset function must be performed.
  8. If all circuits test normal, replace the T18 Battery Charger. If the DTC resets, replace the A4 hybrid/EV battery pack assembly.

Battery Main Bus Diagnostics

  1. Ignition OFF, disable the high voltage at the T6 Power Inverter Module Assembly. Refer to High Voltage Disabling .
  2. Disconnect the F118 hybrid battery pack connector jumper connector at the A28 hybrid/EV battery contactor assembly.
  3. Disconnect the X3 harness connector at the A28 hybrid/EV battery contactor assembly.
  4. Test for infinite resistance between the terminals listed below:
  5. • High-voltage DC (-360 V) negative terminal B X3 harness connector at the A28 hybrid/EV battery contactor assembly to vehicle chassis earth.
    • High-voltage DC (+360 V) positive terminal A X3 harness connector at the A28 hybrid/EV battery contactor assembly to vehicle chassis earth.
    • High-voltage DC (+360 V) positive terminal A X3 harness connector at the A28 hybrid/EV battery contactor assembly and the high-voltage DC (-360 V) negative terminal B X3 harness connector at the A28 hybrid/EV battery contactor assembly.
    If less than the specified value, replace the high-voltage DC cables. After the repair is complete with a scan tool, the Clear Secured High-Voltage DTCs reset function must be performed.
  6. Test for less than 10 Ω between the terminals listed below:
  7. • High-voltage DC (-360 V) negative terminal B X3 harness connector at the A28 hybrid/EV battery contactor assembly and the high-voltage DC (-360 V) negative terminal B X3 harness connector at the T6 Power Inverter Module Assembly.
    • High-voltage DC (+360 V) positive terminal A X3 harness connector at the A28 hybrid/EV battery contactor assembly and the high-voltage DC (+360 V) negative terminal A X3 harness connector at the T6 Power Inverter Module Assembly.
    If greater than the specified value, replace the high-voltage DC cables. After the repair is complete with a scan tool, the Clear Secured High-Voltage DTCs reset function must be performed.
  8. If all circuits test normal, replace the T6 Power Inverter Module Assembly. If the DTC resets, replace the A4 hybrid/EV battery pack assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

    •  Drive Motor Battery Replacement and Shipping Preparation
    • Control Module References for battery energy control module replacement, programming and set-up for the hybrid/EV battery pack replacement.
   


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