DTC 4-2: Green LED Error: Procedure

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

Fig 1: Identifying U46 ECU And W8 Map Light Connector

GTY101401

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

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)