What Does It Mean?
This is a generic diagnostic trouble code (DTC) and applies to many OBD-II vehicles (1996-newer). This may include, but is not limited to, Acura, Audi, Buick, Cadillac, Chevrolet, Chrysler, Ford, Hyundai, Jaguar, Kia, Nissan, Scion, Toyota vehicles, etc. Although generic, the exact repair steps may vary depending on the year, make, model, and powertrain configuration.
A stored code P064F means that the Powertrain Control Module (PCM) has detected an unauthorized or unrecognized software application or a controller calibration error.
Installing factory software and calibrating onboard controllers is often referred to as programming. While most programming is done before the vehicle is delivered to the owner, the onboard controllers continue to adapt to specific circumstances and learn effectively to meet the needs of individual drivers and geographic locations (among others). Factors including voltage spikes, excessive temperatures, and excessive humidity can contribute to software and calibration failure.
Installing aftermarket software may result in a P064F code being stored, but it is usually temporary. Once the PCM has learned the software and the code is cleared, it typically does not reset.
Whenever the ignition is turned on and the PCM is powered, several controller self-tests are performed. By performing controller self-tests, the PCM can monitor serial data that is carried on the Controller Area Network (CAN) to ensure that the onboard controllers interface correctly. Memory functions, as well as software applications, are tested at this time and also tested periodically when the ignition is in the ON position.
If a problem is detected in the monitoring controller’s software/calibration, a P064F code will be stored and a Malfunction Indicator Lamp (MIL) may be illuminated.
A typical Powertrain Control Module PCM, opened:
Powertrain Control Module P064F
How Severe Is This DTC?
A P064F should be considered severe as it can lead to various engine starting and/or driving problems.
What are some of the symptoms of the code?
Symptoms of a P064F trouble code may include:
Engine crank no start or delayed start
Engine driveability issues
Other stored codes
What are some of the common causes of the code?
Causes
of this code may include:
PCM programming error
Faulty controller or PCM
Installation of aftermarket or high-performance software
What are the P064F troubleshooting steps?
Even for the most experienced and well-equipped technician, a P064F code can be particularly difficult to diagnose. Without access to reprogramming equipment, an accurate diagnosis will be virtually impossible.
Consult your vehicle’s information source for Technical Service Bulletins (TSBs) that reproduce the stored code, the vehicle (year, make, model, and engine), and the symptoms presented. If you find the appropriate TSB, it may provide helpful diagnostic information.
Start by connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and freeze frame data. You will want to note this information, just in case the code proves to be intermittent.
After recording all relevant information, clear the codes and test drive the vehicle (if possible) until the code resets or the PCM enters readiness mode.
If the PCM enters readiness mode, the code is intermittent and will be even more difficult to diagnose. The condition that caused the P064F to be stored may need to worsen before an accurate diagnosis can be reached. On the other hand, if the code does not reset and no driveability symptoms manifest, the vehicle may be operating normally.
Test the controller ground integrity by connecting the DVOM’s negative test lead to ground and the positive test lead to battery voltage