Back-up Light Circuit: Procedure

1. Remove the GAUGE NO. 1 fuse from the instrument panel junction block.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   GAUGE NO. 1 fuse	Always	Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

1. Remove the back-up light relay from the engine room No. 2 relay block.
   Fig 1: Measuring Resistance Of Back-Up Light Relay (BK/UP LP)

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

   Standard resistance

   Tester Connection	Specified Condition
   3 - 5	10 kΩ or higher (When battery voltage is not applied to terminals 1 and 2)
   	Below 1 Ω (When battery voltage is applied to terminals 1 and 2)

NG → REPLACE BACK-UP LIGHT RELAY 

OK: Go to next step 

1. Disconnect the A65 hybrid vehicle control ECU connector.
   Fig 2: Checking Harness And Connector (Back-Up Light Relay - Hybrid Vehicle Control ECU And Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Remove the back-up light relay from the engine room No. 2 relay block.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester connection	Condition	Specified value
   A65-15 (BL) - Relay terminal 1	Always	Below 1 Ω
   Relay terminal 2 - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Remove the hybrid vehicle control ECU with its connectors still connected.
2. Measure the voltage according to the value(s) in the table below.
   Fig 3: Measuring Voltage Of Hybrid Vehicle Control ECU

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester connection	Condition	Specified value
   A65-15 (BL) - Body ground	Ignition switch ON Shift lever in R position	11 to 14 V
   	Ignition switch ON Shift lever not in R position	Below 1 V

NG → See step   6 

OK: Go to next step 

1. Remove the back-up light relay from the engine room No. 2 relay block.
   Fig 4: Checking Harness And Connector (Battery - Back-Up Light Relay)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester connection	Condition	Specified value
   Relay terminal 3 - Body ground	Ignition switch ON	11 to 14 V
   Relay terminal 3 - Body ground	Ignition switch off	Below 1 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - BACK-UP LIGHT RELAY) 

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (BULB - BACK-UP LIGHT RELAY AND BODY GROUND)