Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer and the key aren't talking to each other properly, so the car might not start.
The EWS system is responsible for ensuring that only authorized keys can start the vehicle. A telegram error indicates a communication problem between the key and the EWS module.
The P1660 code is triggered when the Electronic Immobilizer System (EWS) detects a communication error in the data exchange between the EWS control unit and the key transponder. This can prevent the vehicle from starting as the EWS is unable to verify the key's authorization.
• Engine does not start
• Security light illuminated on the dashboard
• Intermittent starting issues
• Faulty or damaged key transponder
• Wiring issues between the EWS module and the key reader
• Malfunctioning EWS control unit
EWS: Electronic Immobilizer System
Transponder: A device that transmits a coded signal to the vehicle's immobilizer system.
• Check for any visible damage to the key or key fob.
• Inspect wiring and connections between the EWS module and the key reader.
• Use a diagnostic scanner to check for additional codes and data.
• Replace or repair the key transponder if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the EWS control unit if it is malfunctioning.
• OBD-II diagnostic scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regularly check and maintain key fob battery.
• Avoid exposing the key to extreme temperatures or moisture.
• Ensure regular maintenance of vehicle's electrical systems.
Security System Issue
• Keep a spare key handy in case of key failure.
• Regularly test the spare key to ensure it works.
• Consult with a professional if starting issues persist.
Check with the vehicle manufacturer for warranty coverage on the EWS system.
The P1660 code is commonly associated with BMW vehicles due to their sophisticated electronic immobilizer systems.
High – This issue can prevent the vehicle from starting, leaving you stranded.
Ensure that any repairs or replacements are conducted by a qualified technician to maintain vehicle safety and security.
• Vehicle in 'On' position without starting.
• Attempt to start the vehicle with the key.
The EWS module is typically located under the dashboard or near the steering column.
Q: Can I still drive my car with this code?
A: No, if the P1660 code is active, the vehicle may not start.
Q: Will replacing the key fix the issue?
A: If the key transponder is faulty, replacing the key might resolve the issue. However, further diagnosis may be needed.
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