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

WARNING: This page is about a different car, the 2011 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

CHECK CONNECTOR CONNECTION CONDITION
1. Turn the engine switch off.
2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and the outside electrical key oscillator (for rear side).
  OK
  
  Connectors are properly connected.
NG → CONNECT CONNECTORS PROPERLY

OK: Go to next step

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - OUTSIDE ELECTRICAL KEY OSCILLATOR)

Disconnect the certification ECU (smart key ECU assembly) connector.
Disconnect the outside electrical key oscillator (for rear side) connector.

Fig 1: Certification ECU (Smart Key ECU Assembly) & Outside Electrical Key Oscillator (For Rear Side) Connectors
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
O1-19 (CLG8) - V1-1 (CLG5)	Always	Below 1 Ω
O1-20 (CG8B) - V1-2 (CLGB)	Always	Below 1 Ω
O1-19 (CLG8) - Body ground	Always	10 kΩ or higher
O1-20 (CG8B) - Body ground	Always	10 kΩ or higher
V1-1 (CLG5) - Body ground	Always	10 kΩ or higher
V1-2 (CLGB) - Body ground	Always	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to Certification ECU (Smart Key ECU Assembly))
*2	Front view of wire harness connector (to Outside Electrical Key Oscillator (for Rear Side))

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

INSPECT OUTSIDE ELECTRICAL KEY OSCILLATOR

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

Fig 2: V1 Connector

Standard Resistance

Tester Connection	Condition	Specified Condition
V1-1 (CLG5) - V1-2 (CLGB)	Always	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Component without harness connected (Outside Electrical Key Oscillator (for Rear Side))

NG → See step 6

OK: Go to next step

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
1. Replace the certification ECU (smart key ECU assembly). Refer to REMOVAL .
NEXT: Go to next step
CHECK DTC OUTPUT
1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Recheck for DTCs.
  OK
  
  DTC B27A8 is not output.
NG → See step 6

OK → END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE)
REPLACE OUTSIDE ELECTRICAL KEY OSCILLATOR. Refer to REMOVAL