How to Troubleshoot the Keyless Access System
Self-Diagnostic Function
The keyless access system has a self-diagnostic function. If any malfunction is stored in the keyless access control unit, the DTC codes can be determined by the keyless access indicator blinking pattern.

Short the SCS line with the HDS, then press the engine start/stop button to select the ON mode. The keyless access indicator starts to show the DTCs if any DTCs are stored.

The DTC is cleared when the battery terminal is disconnected, or by removing the No. A21 (10 A) fuse from the under-hood fuse/relay box.

DTC
Keyless access indicator
Description
B1601
1
?
Keyless access ECU CPU error
B1602
2
?
Keyless access ECU EEPROM error
B1632
32
?
MTRCONT signal error
B1640
40
?
RF unit circuit malfunction
B1645
45
?
Driver's Door LF Antenna Circuit Short
B1646
46
?
Driver's Door LF Antenna Circuit Open
B1647
47
?
Passenger's Door LF Antenna Circuit Short
B1648
48
?
Passenger's Door LF Antenna Circuit Open
B1657
57
?
Rear Bumper LF Antenna Circuit Short
B1658
58
?
Rear Bumper LF Antenna Circuit Open
B1659
59
?
Front Interior LF Antenna Circuit Short
B1660
60
?
Front Interior LF Antenna Circuit Open
B1663
63
?
Rear Interior LF Antenna Circuit Short
B1664
64
?
Rear Interior LF Antenna Circuit Open
B1667
67
?
Rear Shelf LF Antenna Circuit Short
B1668
68
?
Rear Shelf LF Antenna Circuit Open
U0199
7
?
Keyless access - P/W communication error
U1280
100
?
Keyless access ECU bus line error
U1281
5
?
Keyless access control unit lost communication with MICU
U128D
10
?
Keyless access control unit lost communication with gauge control module

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