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Inspection Procedure

CHECK WIRE HARNESS (MAYDAY ECU - MAP LIGHT (MAYDAY SWITCH))

Disconnect the U46 ECU connector.
Disconnect the W8 map light connector.

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
U46-11 (IND2) - W8-5 (IND2)	Below 1 Ω
U46-11 (IND2) or W8-5 (IND2) - Body ground	10 kΩ or higher

Fig 1: Identifying U46 ECU Connector And W8 MAP Light Connector

G05300054

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR THEN CLEAR HISTORIC DTC

OK: Go to next step

CHECK OPERATION OF MAYDAY SWITCH ASSEMBLY (GREEN LED)
1. Temporarily replace the Mayday switch with a new or normally functioning one.
2. Check that the system operates normally.
  OK:
  
  Green LED operates normally.
OK: END (MAYDAY SWITCH (GREEN LED) IS FAULTY; CLEAR HISTORIC DTC)

NG: Go to next step
CHECK OPERATION OF MAP LIGHT ASSEMBLY
1. Temporarily replace the map light with a new or normally functioning one.
2. Check that the system operates normally.
  OK:
  
  Green LED operates normally.
NG: REPLACE MAYDAY ECU TOGETHER WITH MAYDAY BATTERY AND THEN PERFORM REGISTRATION

OK: END (MAP LIGHT IS FAULTY; CLEAR HISTORIC DTC)