P0AF7

DTC P0AF7

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 Instructionsprovides an overview of each diagnostic category.

DTC Descriptor
DTC P0AF7
- 14 Volt Power Module Overtemperature

Circuit/System Description

The accessory DC power module controls the energy flowing between the high voltage, 300-volt, DC and low voltage, 14-volt, DC to support the vehicles accessories and charge the 12-volt battery. The accessory DC power control module receives a 14-volt enable command from the hybrid powertrain control module over the serial data communication circuit. Accessory DC power module functions will run only when the accessory DC power module enable is active on the serial data communication circuit.

Conditions for Running the DTC

The Ignition is ON.

Conditions for Setting the DTC

Accessory DC power control module heat plate temperature is greater than 105°C (221°F).

Action Taken When the DTC Sets

* DTC P0AF7 is a Type C DTC.
* The accessory DC power control module will shut down charging or Jump Assist.
* The accessory DC power control module will also set DTC P1A8B 11 42-Volt Inverter Temperature High to limit power to the electric power steering.

Conditions for Clearing the DTC

DTC P0AF7 is a Type C DTC.

Diagnostic Aids

This DTC could be caused by a possible power electronics cooling system failure due to the following:

* Restricted radiator air flow or coolant fans inoperative.
* Restricted power electronics coolant flow or contaminated coolant.
* Inoperative power electronics cooling system water pump.

Reference Information
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 Relearningfor scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool accessory DC power control module heat plate temperature and engine coolant temperature (ECT) parameters in freeze frame data. The accessory DC power control module heat plate temperature reading should be less than 105°C (221°F).

• If the accessory DC power control module heat plate temperature parameter reading was greater than 105°C (221°F) and the engine coolant temperature (ECT) was greater than 125°C (257°F) in freeze frame data, refer to Symptoms - Engine Cooling Symptoms - Engine Cooling and correct that concern first.

2. Inspect for proper coolant level in the hybrid cooling system reservoir.

• If coolant level is low refer to Hybrid Cooling System Loss of Coolant Hybrid Cooling System Loss of Coolant.

3. Inspect hybrid cooling hoses for pinches or obstructions.

• If a concern is found, repair or replace hoses as necessary.

4. Inspect the hybrid cooling system radiator for debris or obstruction. Refer to Engine Overheating Engine Overheating.

• If a concern is found, repair or replace the restricted or damaged components as necessary.

5. Inspect for proper operation of all hybrid system coolant pumps. Refer to Hybrid Cooling System Overheating Hybrid Cooling System Overheating.

• If a concern is found, repair or replace the coolant pumps as necessary.

6. Command the cooling fans through all operating speeds.

• If the cooling fans do not operate in all speeds, refer to Cooling Fan Inoperative Cooling Fan Inoperative.

7. Separate the T6 drive motor generator power inverter module from the K1 accessory DC power control module. Inspect the T6 drive motor generator power inverter module and K1 accessory DC power control module cooling surfaces for excessive corrosion or contamination restriction. Refer to Drive Motor Generator Power Inverter Module Removal and Installation Drive Motor Generator Power Inverter Module Removal and Installation.

• If a corrosion or contamination is found, clean the K1 accessory DC power control module and drive motor generator power inverter module cooling surfaces. If corrosion is severe enough to prevent cleaning of the cooling surfaces replace the K1 accessory DC power control module.
• Replace K1 accessory DC power control module if no concerns are found.

Repair Instructions

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

* Generator Control Module Coolant Pump Replacement
* Hybrid Cooling System Leak Test Hybrid Cooling System Leak Test
* Control Module References Programming and Relearningfor Accessory DC Power Module replacement, programming, and setup