DTC B27A8: Open in Outside Luggage Compartment Electrical Key Antenna Circuit: Procedure

WARNING: This page is about a different car, the 2010 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

CHECK CONNECTOR CONNECTION
1. Turn the engine switch off.
2. Check that the connectors are properly connected to the certification ECU and electrical key antenna (outside luggage).
  OK
  
  Connectors are properly connected.
NG → CONNECT CONNECTORS PROPERLY

OK: Go to next step

CHECK HARNESS AND CONNECTOR (ELECTRICAL KEY ANTENNA - CERTIFICATION ECU)

Disconnect the N21 antenna connector.
Disconnect the F78 ECU connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
N21-1 (CLG5) - F78-19 (CLG8)	Always	Below 1 Ω
N21-2 (CLGB) - F78-20 (CG8B)	Always	Below 1 Ω
F78-19 (CLG8) - Body ground	Always	10 kΩ or higher
F78-20 (CG8B) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

INSPECT ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE)

Remove the outside electrical key antenna (outside luggage). Refer to REMOVAL .

Fig 1: Identifying Outside Electrical Key Antenna (Outside Luggage)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
1 (CLG5) - 2 (CLGB)	Always	Below 1 Ω

NG → See step 6

OK: Go to next step

REPLACE CERTIFICATION ECU
1. Temporarily replace the certification ECU with a new one. Refer to REMOVAL .
NEXT: Go to next step
CHECK FOR DTC
1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Check for DTCs. Refer to DTC CHECK / CLEAR .
  OK
  
  DTC B27A8 is not output.
NG → See step 6

OK → END (CERTIFICATION ECU IS DEFECTIVE)
REPLACE ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE). Refer to REMOVAL