What Does It Mean?
This is a generic diagnostic trouble code (DTC) and applies to many OBD-II vehicles (1996 and newer). This may include, but is not limited to, vehicles from Chrysler, Ford, General Motors, Mercedes-Benz, etc. Although generic, the exact repair steps may vary depending on the year, make, model, and powertrain configuration.
A stored P064A code means that the Powertrain Control Module (PCM) has detected a malfunction in the fuel pump control module.
The fuel pump control module is responsible for supplying and regulating the voltage to the fuel pump relay and the fuel pump. In most cases, the fuel pump controller is integrated into the PCM, but it can also be a standalone module. The fuel pump supplies pressurized fuel to the fuel injection system. It is most often located inside the fuel tank.
Whenever the ignition is turned on and the PCM is powered, several controller self-tests are performed. By conducting internal controller self-tests, the PCM can monitor serial data transmitted over the Controller Area Network (CAN) to ensure that onboard controllers interface correctly.
If a problem is detected while monitoring the fuel pump control module, a P064A code will be stored, and a Malfunction Indicator Lamp (MIL) may illuminate.
A typical fuel pump:
P064A Fuel Pump
How Serious Is This DTC?
Fuel pump control module codes should be taken seriously. A stored P064A code could result in a no-start condition.
What Are Some of the Symptoms of the Code?
Symptoms of a P064A trouble code may include:
- Delayed engine start
- No-start condition
- Engine performance issues
- Other stored codes
What Are Some Common Causes of the Code?
Causes of This Code May Include:
- Faulty fuel pump controller or PCM
- Open voltage supply circuit to the fuel pump control module
- Faulty or triggered fuel pump voltage cutoff switch
- PCM programming error
- Open or shorted fuel pump control circuit
What Are the Troubleshooting Steps for P064A?
A diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information will be needed to diagnose a P064A code.
Consult your vehicle’s information source for Technical Service Bulletins (TSBs) that match the stored code, vehicle (year, make, model, and engine), and presented symptoms. If you find the relevant 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 should note this information in case the code proves to be intermittent. After recording all relevant information, clear the codes and test 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 more difficult to diagnose. The condition that caused the P064A to be stored may need to worsen before an accurate diagnosis can be made. If the code resets, continue with your diagnosis.
Use your vehicle information source to obtain connector face views, connector pinout diagrams, component locators, wiring diagrams, and diagnostic flowcharts related to the code and the specific vehicle.
Check for battery voltage on the fuel pump control circuit using the appropriate wiring diagram and your DVOM. If not present, inspect the fuses and relays in the system and replace faulty parts as needed. If the vehicle is equipped with a fuel pump voltage cutoff switch, test it to ensure it has not been activated or is faulty.
If there is no voltage (and/or ground) on the fuel pump control circuit (and all fuses and relays appear to be functioning correctly), inspect the wiring and harnesses related to the controller. You should also check the chassis and engine ground junctions. Use your vehicle information source to find ground locations for related circuits.
If there is voltage (and ground) on the fuel pump control circuit, inspect the system controllers for signs of water, heat, or collision damage. Any damaged controller (especially by water) should be considered faulty.
If the controller’s power and ground circuits are intact, suspect a faulty controller or a controller programming error. Replacing the controller will require reprogramming.
If the vehicle has been involved in a collision, first check the fuel pump voltage cutoff switch.
Test the integrity of the controller ground by connecting the DVOM’s negative test lead to ground and the positive test lead to battery voltage.