P064B PTO Control Module
OBD-II Trouble Code Technical Description
PTO Control Module
What does that mean?
This is a generic diagnostic trouble code (DTC) and applies to many OBD-II vehicles (1996-newer). That may include but is not limited to vehicles from Chrysler, Ford, General Motors, Mercedes-Benz, Toyota, etc. Although generic, the exact repair steps may vary depending on year, make, model, and powertrain configuration.
A stored code P064B means that the powertrain control module (PCM) has detected a malfunction in the power take off (PTO) control module.
The PTO control module is responsible for initiating various PTO functions. These may include activation of specified lighting, increasing engine RPM (when the PTO is engaged), as well as disengagement of drive wheels (using the transfer case) In most cases, the PTO controller is integrated into the PCM but it may also be a stand-alone module.
The PTO is a feature that is included on many hydraulically operated service vehicles such as wreckers and dump body trucks. It allows a large hydraulic pump to be driven using power from the engine. With the vehicle parked and the engine at idle, a transfer case on the transmission output shaft permits the drive wheels to be disengaged and the pump to be engaged via an auxiliary drive shaft. This system is fairly durable and provides an abundance of power for heavy duty functions such as lifting another vehicle (wrecker) or dumping heavy materials (dump body). There are many specialized applications that use a PTO system besides just wreckers and dump trucks.
Each time the ignition is turned on and the PCM is energized, multiple controller self-tests are performed. By performing controller self-tests, the PCM can monitor serial data that is carried over the controller area network (CAN) to ensure that on-board controllers are interfacing properly.
If a problem is detected in monitoring the PTO control module, a code P064B will be stored and a malfunction indicator lamp (MIL) may be illuminated.
What is the severity of this DTC?
For the sake of safety, PTO control module codes should be taken seriously. A stored code P064B could result in lack of PTO function and may present serious safety hazards.
What are some of the symptoms of the code?
Symptoms of a P064B trouble code may include:
Inoperative PTO Slow and laborious engine starting Engine stall at start-up Engine drivability issues Other stored codesWhat are some of the common causes of the code?
Causes for this code may include:
Faulty PTO controller or PCM Open PTO control module voltage supply circuit PCM programming error Open or shorted PTO control circuitWhat are some P064B troubleshooting steps?
A diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of reliable vehicle information will be required to diagnose a code P064B.
Consult your vehicle information source for technical service bulletins (TSB) that replicate the code stored, vehicle (year, make, model, and engine), and symptoms exhibited. If you find the appropriate TSB, it may yield helpful diagnostic information.
Begin by connecting the scanner to the vehicle diagnostic port and retrieving all stored codes and freeze frame data. You will want to write this information down, just in case the code proves to be an intermittent one. After recording all pertinent information, clear the codes and test drive the vehicle (if possible) until the code is reset or the PCM enters readiness mode.
If the PCM enters readiness mode, the code is intermittent and will be more difficult to diagnose. The condition, which caused the P064B to be stored, may need to worsen before an accurate diagnosis can be reached. If the code is reset, continue with your diagnosis.
Use your source of vehicle information to obtain connector face vie
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