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Home >> Acura >> 2017 >> RLX Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Keyless Access Control Unit - Diagnostics (Except Hybrid) >> How to Information >> How to Troubleshoot the Keyless Access System (2018 2019 2020) >> Self-Diagnostic Function
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Self-Diagnostic Function

The keyless access system has a self-diagnostic function. If any malfunction and DTC are stored in the keyless access/TPMS control unit, the keyless access indicator flashes.

When malfunction is detected, the keyless access indicator flashes until the vehicle is turned to the OFF (LOCK) mode.

The DTC is cleared when the battery terminal is disconnected, or by removing the No. C16 fuse .

DTC Keyless access indicator Description
B1601  o Keyless Access Control Unit Internal (CPU) Error
B1602  o Keyless Access Control Unit Internal (EEPROM) Error
B12C5 o Engine Start/Stop Switch Failure
B12D0 o Power Control Unit IG1A Circuit Error
B12D1 o Power Control Unit IG1B Circuit Error
B12D2 o Power Control Unit IG2 Circuit Error
B12D3 o Power Control Unit IG Latch Circuit Error
B1640  o RF1 Antenna Not Connected or Malfunction
B1645  o Driver's Door LF Antenna Circuit Short
B1646  o Driver's Door LF Antenna Circuit Open
B1647  o Passenger's Door LF Antenna Circuit Short
B1648  o Passenger's Door LF Antenna Circuit Open
B1649  o Driver Side Rear Passenger Door Antenna Circuit Short
B1650  o Driver Side Rear Passenger Door Antenna Circuit Open
B1651  o Passenger Side Rear Passenger Door Antenna Circuit Short
B1652  o Passenger Side Rear Passenger Door Antenna Circuit Open
B1659  o Front Interior LF Antenna Circuit Short
B1660  o Front Interior LF Antenna Circuit Open
B1663  o Rear Interior LF Antenna Circuit Short
B1664  o Rear Interior LF Antenna Circuit Open
B12F3 o Power Control Unit Lost Communication With Transmission Control Unit
B1926 o Backup Control Antenna Open or Short
B1931 o Backup Control Unit No Response

NOTE:  When the engine start/stop switch button is pressed and the mode changes to ON, the keyless access indicator comes on when any malfunction is detected.