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P0D21




DTC P0D21, P0D23, P1EF0, or P1EF1

Diagnostic Instructions

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

DTC Descriptors
DTC P0D21
- Battery Charger Output Voltage Too Low

DTC P0D23
- Battery Charger Output Shorted

DTC P1EF0
- Battery Charger High Voltage Converter 1 Output Power Regulation Performance

DTC P1EF1
- Battery Charger High Voltage Converter 2 Output Power Regulation Performance

Circuit/System Description

The hybrid/EV powertrain control module 2 and battery charger control module monitor the battery charger high voltage output and current output and ensures it is in the proper range and there is not a resistive short in the charging bus.

Conditions for Running the DTC

P0D21
* The vehicle 12 V battery system voltage needs to be above 9 V.
* Battery charger in heating mode ONLY:

- Multi-function contactor must be commanded Open.
- Battery charging contactors must be commanded Closed.
- Commanded high voltage current must be greater than 0.5 A.
- High voltage battery heater duty cycle must be greater than 5%.
- Drive motor battery charger cable must be connected and vehicle receiving power.

* All other battery charging modes:

- Multi-function contactor and battery charging contactors must be commanded Closed.
- Drive motor battery charger cable must be connected and vehicle receiving power.

P0D23
* The vehicle 12 V battery system voltage needs to be above 9 V.
* There can not be any high voltage or current sensor faults present.
* The battery charge system must be in the pre-charge state, and the multi-function contactor must be commanded Open.
* There can not be any high voltage battery heating or cooling requests active.
* drive motor battery charger cable must be connected and vehicle receiving power.

P1EF0
* P0D53, P0D54, P0D4E, P0D4F, P1EEB, or P1EEC should not be set.
* The vehicle 12 V battery system voltage needs to be above 9 V
* The vehicle is connected to a 120 V AC supply and the battery charger is converting power.

P1EF1
* P0D53, P0D54, P0D4E, P0D4F, P1EEB, or P1EEC should not be set.
* The vehicle 12 V battery system voltage needs to be above 9 V
* The vehicle is connected to a 240 V AC supply and the battery charger is converting power.

Conditions for Setting the DTC

P0D21

Battery charger high voltage output voltage is less than 150 V for about 1 second.

P0D23

The battery charger high voltage output current exceeds 0.1 A for about 3 seconds.

P1EF0 or P1EF1

The battery charger actual high voltage output voltage or current is out of the allowable tolerance compared with the commanded output voltage or current. This is measured internal to the battery charger.

Action Taken When the DTC Sets

P0D21
* DTC P0D21 is a type B DTC.
* Disables the high voltage battery heating and/or charging.

P0D23, P1EF0, or P1EF1
* DTC P0D23 is a type A DTC.
* Disables the high voltage battery charging.

Conditions for Clearing the DTC

P0D21

DTC P0D21 is a type B DTC.

P0D23, P1EF0, or P1EF1

DTC P0D23 is a type A DTC.

Diagnostic Aids

Low or unstable household voltage supply can cause this DTC to set. Verify with customer that household voltage was not fluctuating during charge attempt and that they are using a dedicated circuit. Voltage fluctuations can be indicated by intermittent red LEDs on the drive motor battery charger cable.

Reference Information
Schematic Reference

Plug-In Charging Schematics Plug-In Charging Schematics
Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1
Description and Operation

Plug-In Charging System Description and Operation Description and Operation
Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference

Control Module References Programming and Relearning for scan tool information
Special Tools

EL-48900 - HEV Safety Kit

For equivalent regional tools, refer to Special Tools Tools and Equipment.

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 will perform the following tasks:


* 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 exactly as written may result in serious injury or death.


1. Verify no battery-related DTCs are set.

• If any battery-related DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for hybrid battery diagnostics.

2. Clear DTC, connect the drive motor battery charger cable to vehicle and known good household supply voltage.
3. Verify DTC P0D21,P0D23, P1EF0, or P1EF1 is set.

• If DTC is not set, vehicle owner will have to attempt charge at home again. If the vehicle will not charge they will need electrical supply serviced.

4. Vehicle OFF, disable the high voltage at the A4 hybrid/EV battery pack and the T18 battery charger. Refer to High Voltage Disabling High Voltage Disabling.
5. Disconnect the X4 connector at the T18 battery charger and at the X5 connector at the A4 hybrid/EV battery pack.
6. Test for infinite resistance between the 300 V circuit terminals listed below and ground:

* Terminal A X4
* Terminal B X4

• If less than the specified range, test the 300 V circuit for a short to ground.

7. Test for less than 10 ohm between the 300 V circuit terminals listed below:

* T18 battery charger terminal A X4 and A4 hybrid/EV battery pack A X5
* T18 battery charger terminal B X4 and A4 hybrid/EV battery pack B X5

• If greater than the specified range, test the 300 V circuit for an open/high resistance.

8. Test for infinite resistance between the 300 V circuit terminal A X4 and B X4.

• If less than the specified range, test the 300 V circuits for a short between the circuits.

9. If all circuits tests normal, replace the T18 battery charger.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Control Module References Programming and Relearning for battery charger control module replacement, programming and setup

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