Engine Switch Indicator Circuit: Procedure

1. Remove the engine switch, refer to REMOVAL .
   Fig 1: Identifying Engine Switch Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Apply battery voltage between the terminals of the switch, and check the illumination condition of the switch.
   NOTE:

   • If the positive (+) lead and the negative (-) lead are incorrectly connected, the engine switch indicator will not illuminate.
   • If the voltage is too low, the indicator will not illuminate.

   OK

   Measurement Condition	Specified Condition
   Battery positive (+) → Terminal 11 (SWIL) Battery negative (-) → Terminal 4 (COM) or 5 (GND)	Illuminates
   Battery positive (+) → Terminal 12 (INDS) Battery negative (-) → Terminal 4 (COM) or 5 (GND)	Illuminates
   Battery positive (+) → Terminal 13 (INDW) Battery negative (-) → Terminal 4 (COM) or 5 (GND)	Illuminates

NG → See step   3 

OK: Go to next step 

1. Disconnect the D25 switch connector.
   Fig 2: Identifying D25 Switch & D8 ECU Connectors Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the D8 ECU connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   D25-11 (SWIL) - D8-25 (SWIL)	Always	Below 1 Ω
   D25-12 (INDS) - D8-15 (INDS)
   D25-13 (INDW) - D8-14 (INDW)
   D25-5 (GND) - Body ground
   D25-4 (COM) - Body ground
   D25-11 (SWIL) or D8-25 (SWIL) - Body ground		10 kΩ or higher
   D25-12 (INDS) or D8-15 (INDS) - Body ground
   D25-13 (INDW) or D8-14 (INDW) - Body ground

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK)