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 car's security system, which prevents it from being stolen, is having trouble reading or writing important information. It's like when your computer can't save or open a file properly.
The P1664 code indicates a problem with the electronic immobilizer system's EEPROM, which is responsible for storing key data that allows the car to start.
The EEPROM (Electrically Erasable Programmable Read-Only Memory) in the Electronic Immobilizer System (EWS) is used to store data related to the vehicle's security system. A P1664 code is triggered when there is a failure in reading or writing data to this memory, which can prevent the vehicle from recognizing the correct key and starting the engine.
• Engine does not start
• Security light is illuminated on the dashboard
• Intermittent starting issues
• Faulty EEPROM in the EWS module
• Corrupted data in the EEPROM
• Wiring issues or poor connections to the EWS module
EEPROM: Electrically Erasable Programmable Read-Only Memory
EWS: Electronic Immobilizer System
• Check for other related codes
• Inspect the wiring and connections to the EWS module
• Test the EEPROM for faults
• Reprogram or replace the EEPROM
• Repair or replace faulty wiring
• Replace the EWS module if necessary
• OBD-II scanner
• Multimeter
• EEPROM programmer
$200 - $600
Difficult
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regularly check and maintain the vehicle's electrical system
• Avoid exposing the vehicle to extreme temperatures
• Ensure the vehicle's battery is in good condition
Security System Issue
• Do not attempt to start the vehicle repeatedly, as it may drain the battery.
• Consult with a professional mechanic or dealership for diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on the EWS module.
This code has been more prevalent in older BMW models with the EWS system, particularly those manufactured in the late 1990s and early 2000s.
High – This issue can prevent the vehicle from starting, requiring immediate attention.
Driving with a malfunctioning immobilizer system can leave the vehicle vulnerable to theft. Ensure repairs are conducted by a qualified technician.
• Vehicle in a secure location
• Access to the EWS module
The EWS module is typically located under the dashboard on the driver's side or near the steering column.
Q: Can I drive my car with a P1664 code?
A: No, this code usually means the car won't start, so it needs to be fixed before you can drive it.
Q: Is this a common issue?
A: It's relatively common in older BMW models with the EWS system, particularly if the vehicle has electrical issues.
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