Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's system that helps keep the car at a steady speed isn't working because it can't find any signals to control it.
The Adaptive Cruise Control system is not detecting any activity or input, which means it cannot function properly.
The P1677 code indicates that the Adaptive Cruise Control (ACC) system is not receiving any signals or inputs necessary for its operation. This could be due to a communication failure, sensor issue, or a problem with the ACC module itself.
• ACC system not working
• Warning light on dashboard
• Inability to maintain set speed
• Faulty ACC module
• Wiring issues or poor connections
• Faulty radar or sensor
ACC: Adaptive Cruise Control
OBD-II: On-Board Diagnostics, Second Generation
• Check for any other related codes
• Inspect wiring and connections to the ACC module
• Test the radar and sensors for proper operation
• Repair or replace faulty wiring
• Replace the ACC module if necessary
• Calibrate or replace faulty sensors
• OBD-II scanner
• Multimeter
• Diagnostic software
$200 - $800
Moderate
• Honda Accord
• Toyota Camry
• Ford Fusion
• Regular maintenance checks
• Ensure sensors are clean and unobstructed
• Check wiring and connections periodically
Sensor Issue
• Avoid using cruise control until fixed
• Get the vehicle checked by a professional
• Monitor for any additional warning lights
Check with the vehicle manufacturer for specific warranty coverage related to electronic systems.
This code has been associated with issues in vehicles equipped with early versions of Adaptive Cruise Control systems.
Moderate – The vehicle can still be driven, but the ACC feature will not function until repaired.
Driving without a functioning ACC system may result in reduced convenience and safety features. Always maintain control of the vehicle manually.
• Vehicle must be in motion
• ACC system must be activated
The ACC module is typically located behind the front grille or bumper, where it has a clear view of the road ahead.
Q: Can I drive my car with this code?
A: Yes, but the Adaptive Cruise Control feature will not work.
Q: Will this code affect my car's performance?
A: It won't affect basic driving, but you won't be able to use the cruise control feature.
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