Error Code P064A is defined as Fuel Pump Control Module. This is a generic trouble code, meaning it applies to all vehicles equipped with the OBD-II system. This includes vehicle models from Chrysler, Ford, GMC, Mercedes Benz, etc. Specifications on the definition, troubleshooting, and repairs, of course, vary from make, model, and powertrain configuration.
The job of the fuel pump control module is to supply and regulate the voltage that comes to the fuel pump relay and fuel pump. For most cases, the fuel pump controller is integrated straight to the PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes), but it can also be a stand-alone module for some vehicles. Usually found inside the fuel tank, the fuel pump provides pressurized fuel for the fuel injection system.
Whenever the ignition is turned on, and the PCM is energized, various controller self-tests are simultaneously performed. Aside from running internal controller self-test, the CAN (controller area network) carries serial data from each module to make sure the onboard controllers are interfacing properly.
Error Code P064A means the PCM has determined a malfunction in the fuel pump control module. Also simultaneously activate the Check Engine light.
As with most error codes, this code activates the Check Engine light. In some cases though, it may not turn on. Other common symptoms include:
- No start or delayed engine starting
- Engine drivability problems
Other stored codes may also be stored.
- Faulty fuel pump controller
- Faulty or bad programming in PCM
- Open fuel pump control module voltage supply circuit
- Open or shorted fuel pump control circuit
- Bad or tripped fuel pump voltage shutoff switch
How to Check
Checking this code requires a DVOM (digital volt ohmmeter), dependable vehicle information for TSB (technical service bulletin) that has the code stored, vehicle (year, make, model, engine), and exhibited symptoms. Finding the right TSB can lead you to more easy and successful diagnostic and repair procedure.
Start by connecting the scanner to the vehicle diagnostic port. Retrieve all the stored data including freeze frame data. Write down this information. Then, clear the codes and then take the vehicle for a test drive until the code reset, or the PCM enter readiness mode.
If the PCM enters readiness mode, that means the problem is intermittent. You may have to wait for the problem to get worse before you can successfully diagnose and repair. If the code resets on the other hand, then continue with the diagnosis.
Use the vehicle information to know the connector pin-out charts, face views, component locators, wiring diagrams, and diagnostic flow charts of the vehicle.
Use the diagram and DVOM to check the voltage of the battery on the speed control warning lamp circuit. If there’s none, check the system fuses and relays. Replace the defective parts as necessary.
If there is a voltage at the speed control warning lamp, then you can suspect a defective speed control warning lamp bulb.
If the speed control warning lamp bulb is working properly, and this code still resets, then use the DVOM to test the controller power supply fuses and relays. Replace as needed; fuses must be tested with the circuit loaded.
If all fuses and relays look good, then inspect the controller related wiring and harness. Check the chassis and engine ground junctions as well. Use your vehicle information source to locate ground for related circuits.
Also, check the system controllers; look for signs of damage, water intrusion, heat, or collision damage. Damaged controllers, especially those damaged by water, is considered defective and must be replaced.
If the controller power and ground circuits are in good shape, then you can suspect a defective controller or a programming error. In which case, controller replacement will be required, as well as reprogramming.
In some cases, you may want to purchase a reprogrammed controller from aftermarket sources. Other vehicles/controllers require onboard reprogramming that may be done through a dealership, or by a qualified technician.
How to Fix
Depending on the diagnosis, common repairs for this code include:
- Replacement of damaged or burnt bulb or LED
- Replacement of damaged or corroded wiring and related electrical connectors
- Repair or replacement of damaged terminals (straighten bent pins)
- Replacement of burnt out fuse(s)
Since this code affects the vehicle’s driving operation, it’s considered as a potentially serious code. Thus, when it appears, it’s recommended to take the vehicle in question to the local service center or qualified mechanic for proper diagnosis and repair.
If the vehicle has been involved in a collision, it’s important to check the fuel pump voltage interrupt switch as soon as possible. It’s important to test the integrity of the controller ground by connecting its negative test lead of the DVOM to ground, and a positive test lead to the battery voltage.