Inspection Procedure

CHECK WIRE HARNESS (ECU - ROOF CONSOLE BOX ASSEMBLY (MAYDAY SWITCH ASSEMBLY))

Disconnect the M16 ECU connector.
Disconnect the O2 roof console box connector.

Fig 1: Identifying Roof Console Box & Mayday ECU Connector Terminals

G05266644

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Measure the resistance of the wire harness side connectors.
Standard resistance

RESISTANCE SPECIFICATION TABLE

Tester Connection	Specified Condition
M16-4 (IND1) - O2-16 (IND1)	Below 1 Ω
M16-4 (IND1) or O2-16 (IND1) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

REPLACE ROOF CONSOLE BOX ASSEMBLY
1. Temporarily replace the roof console box assembly (See REMOVAL ) with a new or normally functioning one.
2. Check that the system operates normally.
  OK:
  
  Red LED operates normally.
  
  NOTE: If replacement of the ECU is necessary, replace the mayday battery (backup battery) together with the ECU. After the replacement, register the ECU (See REGISTRATION ).
  
  NG: REPLACE MAYDAY ECU ASSEMBLY (See REMOVAL )
OK: END