DTC B27C0-57: Digital Key System Invalid/Incompatible Software Component [12/2024 - ]: Description

2025 Toyota 4Runner SR5, RWDSECTION Description

This DTC is output when 1 or more electrical key transmitter sub-assemblies are registered and MAC data mismatch was detected 10 times in succession from the digital key computer assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from Priority Note
B27C0-57 Digital Key System Invalid/Incompatible Software Component 1 or more electrical key transmitter sub-assemblies are registered and MAC data mismatch was detected 10 times in succession from the digital key ECU assembly
  • Certification ECU (smart key ECU assembly)
  • Digital key ECU assembly
  • Wire harness or connector
Smart Key A DTC Output Confirmation Operation: 
  1. Any time
VEHICLE CONDITION AND FAIL-SAFE OPERATION WHEN MALFUNCTION DETECTED

Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Digital key system does not operate -
RENDER: 1.0x

NO RELATED

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