P0AC4 Code – Hybrid Powertrain Control Module Requested MIL Illumination

Control modules constantly monitor the vehicle for any condition which may adversely affect vehicle performance. If a condition is detected, the module sets a Diagnostic Trouble Code (DTC) and sends a serial data message to the Engine Control Module (ECM). The P0AC4 occurs due to problems in the hybrid powertrain control module. This article explains the P0AC4 causes, symptoms, and meaning.

P0AC4 Definition

P0AC4 Code – Hybrid Powertrain Control Module Requested MIL Illumination

What Does the P0AC4 Code Mean?

The P0AC4 code would start indicating that the hybrid powertrain control module has set an emission associated hybrid powertrain code.

P0AC4 Code

The hybrid powertrain control module would send a message via serial data circuit to the engine control module (ECM) requesting illumination of the Malfunction Indicator Light (MIL).

When the engine control module receives this message, then the P0AC4 fault code trigs up. 

Causes of OBD Code P0AC4

  • Defaults in the hybrid powertrain control module
  • A hybrid powertrain control module circuit might have a poor electrical connection.
  • The hybrid powertrain control module harness might be opened or shorted

Symptoms Of Code P0AC4

As the P0AC4 code occurs, it gives one of the below-given symptoms:

  1. The check engine light starts illuminating
  2. A reduction in fuel economy
  3. Reduction in the engine performance

Read More: Causes and Symptoms of P0506

How to diagnose the P0AC4 Code?

Follow the below-given steps to diagnose the P0AC4:

  • Scan all the trouble codes from the PCM of the car through the OBD-II scanner.
  • Examine the freeze frame data to analyze the status of the engine at the setting time of the trouble code.
  • Check for wires and connectors that might be rubbed through, disconnected, or loose. It is also important to check the fuse box in your vehicle and the relay centre that can be found under the hood.
  • Carefully inspect the hybrid powertrain control module and make sure to repair or replace it if found faulty.
  • It is also important to make sure that the fuses are good. Make sure that no melted plastic can cause a fire.
  • Once you have completely checked all the obvious things and still can’t find the right solution, then you have to begin suspecting either the computer or the sensor.

How to Fix P0AC4 Code

  • Before the proper diagnostic of P0506, always Search for all trouble codes and diagnose them thoroughly.
  • Check the damaged wiring between your car.
  • It is essential to restore the flawed hybrid powertrain control module
  • Rehabilitate the defaults in the ECM
  • Repair or replace the quirky hybrid powertrain control module circuit
  • The hybrid powertrain control module harness should be restored to working order

What repairs can fix the P0AC4

  1. Engine Control Module: Is your car engine light still staying ON after resetting, or your car engine is turning off for no reason? If yes, then it is a symptom indicating that your car engine control module is defective.
  2. Electronic Control Unit: The ECU is a major component of your car’s onboard computer. It’s used to regulate many systems and subsystems in your car’s engine, drive train, and other major components. Visit us to buy the best quality ECU online.
  3. Hybrid Battery: Faulty hybrid batteries may overheat or discharge quickly, causing drivability issues. It can affect the acceleration and throttle response and can also cause damage to various parts. Replace the faulty hybrid battery now!
  4. Diagnostic Tool: Find high-grade diagnostic tools to detect the OBD error code from us. Visit us today to grab amazing deals.
  5. PCM: The PCM works as the central computer system in an automobile’s mechanism. This auto part is in charge of all the constituents as well as the functions performed by them. Having such enormous importance in the operation of all the parts means that any defect in it will affect almost every aspect of a car.
  6. Throttle Body: Clean dirty throttle body.
  7. Wiring: Repair or replace the damaged electric wiring.

 P0AC4 Repair Cost

The repair cost of the P0AC4 varies according to the vehicle model and labor cost. The average repair or fixing cost of the P0AC4 code is from $890 to $970.

FAQ Section

What is a hybrid powertrain control module?

In the event of bearing damage, the Hybrid Powertrain Control Module (HPCM) detects the overheat condition and initiates failsafe mode, which cuts drive power to both the engine and electric motor. Without drivetrain power, the customer may experience an engine stall while driving, increasing the risk of a crash.

What is battery module deterioration?

The battery will deteriorate over time and is monitored by a dedicated control module. The battery resistance increases with deterioration, and the Engine Control Unit (ECU) will activate this engine code when it detects the resistance exceeding the standard range.

What does code P1E00 mean?

P1E00 is a blanket code – light the MIL (Malfunction Indicator Light – Check Engine Light).

Read More
  1. Symptoms of bad ECU
  2. Causes and Symptoms of P0017
  3. Causes and Symptoms of P0016
  4. Function of PCM (Powertrain Control Module)
  5. Symptoms of bad EGR SEnsor 

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