Luggage Room Junction Block ECU Power Source Circuit: Procedure

1. Remove the AM1 and MPX-IG fuses from the driver side junction block.
2. Remove the MPX-B3 fuse from the passenger side junction block.
3. Remove the FUEL OPN fuse from the luggage room junction block.
4. Remove the D/C CUT fuse from the engine room No. 1 relay block.
5. Measure the resistance of the fuses.

   Standard resistance

   Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

Fig 1: Identifying Defogger Relay Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the IG1 relay from the driver side junction block.
2. Measure the resistance of the relay.

   Standard resistance

   Tester Connection	Specified Condition
   3 - 5	10 kΩ or higher
   3 - 5	Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

NG → REPLACE IG1 RELAY 

OK: Go to next step 

Fig 2: Identifying Luggage Room Junction Block And Luggage Room Junction Block ECU

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the 6A, 6F and 6L junction block connectors.
2. Disconnect the L24 ECU connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance

   Tester Connection	Specified Condition
   6A-2 - Body ground	Below 1 Ω
   6A-5 - Body ground	Below 1 Ω
   L24-5 (SG) - Body ground	Below 1 Ω

4. Measure the voltage of the wire harness side connector.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   6F-12 - Body ground	Always	10 to 14 V
   6L-1 - Body ground	Always	10 to 14 V
   6F-13 - Body ground	Ignition switch ON	10 to 14 V

NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK → REPLACE LUGGAGE ROOM JUNCTION BLOCK