What Does Code P06AF Mean?

The P06AF code is a generic diagnostic trouble code (DTC) that applies to many OBD-II vehicles (1996 and newer models), including but not limited to Buick, Cadillac, Chevrolet, GMC, VW, Ford, etc.

Although this code is generic, the exact repair steps may vary depending on the year, make, model, and powertrain configuration.

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Technical Description

When this code is stored, it means the Powertrain Control Module (PCM) has detected an anomaly in the vehicle’s torque management system. This anomaly is severe enough for the PCM to consider an engine shutdown necessary or justified.

⚠️ Engine torque management codes only apply to vehicles with automatic transmissions.

The torque management system is designed to reduce engine torque during gear shifts in automatic transmissions. This helps preserve the transmission and its components.

The PCM controls this system based on data from several sensors:

• Throttle Position Sensor (TPS)

• Transmission Input and Output Speed Sensors

• Mass Air Flow (MAF) Sensor

When these sensors detect certain conditions, the PCM applies a torque reduction strategy, typically by retarding ignition timing. If the PCM fails to apply this strategy or torque cannot be controlled, code P06AF is stored.

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Code Severity

Torque management systems are not essential for the vehicle’s proper operation. Most drivers don’t even notice when this system isn’t working.

However, this code is considered severe only because of its ability to cause a complete engine shutdown if necessary.

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Possible Symptoms

A P06AF code can cause:

• Engine not starting

• Engine hesitation or stalling

• Driving issues

• Irregular gear shifts

• Harsh gear shifts

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Possible Causes

Common causes of code P06AF include:

• Faulty input or output speed sensor

• Faulty torque converter

• Severe mechanical transmission failure

• Open or shorted wiring or connectors

• Faulty or improperly programmed PCM

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Diagnostic and Troubleshooting Steps

1. Check for other stored codes
   Prioritize those related to torque management. Resolve them before addressing P06AF.

2. Search for Technical Service Bulletins (TSBs)
   They can quickly guide you to a known solution.

3. Use an OBD-II scanner and a digital voltmeter (DVOM)

   • Note all codes and freeze frame data.

   • Clear the codes, then perform a road test.

   If the code does not return, it is likely intermittent. Otherwise, continue diagnostics.

4. Access wiring diagrams and locate related components

   • Visually inspect wires and connectors.

   • Repair or replace any that are damaged, burnt, or corroded.

5. Check PCM power supplies and grounds

   • Test fuses and relays under active load.

   • Replace any faulty components.

6. Suspect a faulty PCM if everything else is good

   • Replacement often requires reprogramming.

   • Some reprogrammed modules are available as replacements, others require dealer reprogramming.

7. Inspect control modules for signs of moisture, heat, or impact
   Any module showing these signs is potentially faulty.

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Important Note

Performance programmers or third-party reprogramming systems can disable certain torque management functions. This may cause code P06AF to appear even if no component is actually faulty.