Inspection Procedure

1. Disconnect the M15 ECU connector.
2. Disconnect the O4 map light plate connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   RESISTANCE SPECIFICATIONS
   
   

   Tester Connection	Specified Condition
   M15-11 (IND2) - O4-12 (IND2)	Below 1 Ω
   M15-11 (IND2) or O4-12 (IND2) - Body ground	10 kΩ or higher

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

Fig 1: Identifying M15 ECU And O4 Map Light Plate Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step 

1. Temporarily replace the mayday switch assembly with a new or normally functioning one.
2. Check that the system operates normally.

   OK: 

   Green LED operates normally. 

OK: END (MAYDAY SWITCH ASSEMBLY (GREEN LED) IS FAULTY; CLEAR HISTORIC DTC) 

NG: Go to next step 

1. Temporarily replace the map light plate assembly with a new or normally functioning one.
2. Check that the system operates normally.

   OK: 

   Green LED operates normally. 

NG: REPLACE MAYDAY ECU ASSEMBLY TOGETHER WITH MAYDAY BATTERY AND THEN PERFORM REGISTRATION 

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