Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the computer in your car, which helps control the engine, has a problem with its memory. It's like when a computer has a glitch and needs to be restarted.
The P1640 code indicates that there is an error in the internal memory of the car's control module, specifically in the RAM or ROM.
The control module, often referred to as the Engine Control Unit (ECU), uses RAM (Random Access Memory) and ROM (Read-Only Memory) to store and process data necessary for engine management. An error in these memory components can lead to improper engine operation or failure to start.
• Check Engine Light is on
• Engine may not start
• Poor engine performance
• Faulty ECU
• Corrupted software or firmware
• Electrical issues such as poor connections or short circuits
ECU: Engine Control Unit, the computer that manages engine functions.
RAM: Random Access Memory, used for temporary data storage.
ROM: Read-Only Memory, used for permanent data storage.
• Use an OBD-II scanner to confirm the code.
• Inspect the ECU for any visible damage or loose connections.
• Check the vehicle's battery and electrical system for issues.
• Reset the ECU by disconnecting the battery for a few minutes.
• Update or re-flash the ECU software.
• Replace the ECU if it is determined to be faulty.
• OBD-II scanner
• Multimeter
• Basic hand tools
$300 - $1200
Difficult
• Chevrolet Silverado
• GMC Sierra
• Pontiac Grand Prix
• Regularly update ECU software.
• Ensure battery and electrical connections are secure.
• Avoid aftermarket modifications that can affect the ECU.
Engine Performance
• Avoid driving the vehicle until the issue is resolved.
• Consult a professional mechanic for a proper diagnosis.
ECU-related issues may be covered under the vehicle's powertrain warranty. Check with the manufacturer.
The P1640 code has been associated with vehicles from the late 1990s to early 2000s, often due to aging ECUs.
High – This issue can prevent the vehicle from starting or running properly.
Driving with a faulty ECU can lead to unexpected engine behavior, which may be unsafe.
• Vehicle must be at operating temperature.
• All electrical systems should be functional.
The ECU is typically located in the engine bay or under the dashboard on the passenger side.
Q: Can I drive with a P1640 code?
A: It's not recommended as it can lead to engine performance issues or failure to start.
Q: Will resetting the ECU fix the P1640 code?
A: Resetting may temporarily clear the code, but if the underlying issue isn't fixed, the code will likely return.
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