Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's security system, which helps prevent theft, is having trouble remembering a special code that changes every time you start the car.
The EWS system uses a rolling code for security. If the code storage in the EEPROM is faulty, the vehicle may not start because the system cannot verify the key.
The EWS (Electronic Immobilizer) system is designed to prevent unauthorized starting of the engine. It uses a rolling code that changes each time the vehicle is started. This code is stored in the EEPROM (Electrically Erasable Programmable Read-Only Memory). A fault in this storage can prevent the system from recognizing the key, causing a no-start condition.
• Engine will not start
• Security light on the dashboard
• Intermittent starting issues
• Faulty EEPROM
• Corrupted rolling code data
• EWS module failure
EWS: Electronic Immobilizer System
EEPROM: Electrically Erasable Programmable Read-Only Memory
• Check for other related fault codes
• Inspect the EWS module and connections
• Test the EEPROM for faults
• Reprogram or replace the EEPROM
• Replace the EWS module if faulty
• Ensure all connections are secure
• OBD-II scanner
• Multimeter
• EEPROM programmer
$150 - $500
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regularly check and maintain the vehicle's electrical system
• Avoid using aftermarket keys or alarm systems
• Ensure software updates are performed by a professional
Security System Issue
• Avoid multiple attempts to start the car if it doesn't start initially
• Consult a professional mechanic for diagnosis
• Keep a spare key available
Check with the vehicle manufacturer for specific warranty coverage on the EWS system.
This code is more common in older vehicles with early electronic immobilizer systems.
High – This issue can prevent the vehicle from starting, potentially leaving you stranded.
Ensure all repairs are performed by qualified personnel to avoid compromising vehicle security.
• Vehicle in parked position
• Key in ignition
The EWS module is typically located near the steering column or under the dashboard.
Q: What happens if the EEPROM is faulty?
A: If the EEPROM is faulty, the car may not start because it cannot verify the key.
Q: Can I fix this issue myself?
A: This issue typically requires specialized tools and knowledge, so it's best handled by a professional.
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