Inspection Procedure

1. Operate the light control rheostat and check that the illumination of the radio and player, center cluster module switch, etc. change accordingly.

   OK: The illumination can be adjusted. 

NG : Go to step   6 

OK : GO TO NEXT STEP 

1. Disconnect the C10 meter connector.
2. Measure the voltage of the wire harness side connector.

   Standard voltage 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   C1-12 (ILL+) - Body ground	Ignition switch is ON and light control switch is at TAIL or HEAD	10 to 14 V

   Fig 1: Disconnecting C10 Meter Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK : GO TO NEXT STEP 

1. Disconnect the C11 meter connector.
2. Disconnect the R6 rheostat connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Specified Condition
   C11-7 (ILL-) - R6-3 (-)	Below 1 Ω

   Fig 2: Disconnecting R6 Rheostat Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK : GO TO NEXT STEP 

1. Disconnect the R6 rheostat connector.
2. Measure the voltage of the wire harness side connector.

   Standard voltage 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   R6-3 (-) - Body ground	Ignition switch is ON and light control switch is at TAIL or HEA	10 to 14 V

   Fig 3: Disconnecting R6 Rheostat Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPLACE COMBINATION METER ASSEMBLY 

OK : GO TO NEXT STEP 

1. Remove the combination meter but do not disconnect the connectors.
2. Turn the ignition switch ON.
3. Using an oscilloscope, check the signal waveform of the meter.
   item content
   
   

   Item	Contents
   Terminal No.	C11-7 (ILL-) - Body ground
   Tool setting	2 V/DIV., 1 msec./DIV.
   Vehicle condition	Ignition switch ON

   Fig 4: Checking Combination Meter Assembly (Ill- Voltage) Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: As shown in the illustration. 

   HINT:

   Waveform changes as illumination dims ("A" becomes longer).

NG : REPLACE LIGHT CONTROL RHEOSTAT 

OK : REPLACE COMBINATION METER ASSEMBLY 

1. Disconnect the R6 rheostat connector.
2. Measure the voltage of the wire harness side connector.

   Standard voltage 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   R6-1 (IG) - Body ground	Ignition switch is ON	10 to 14 V
   R6-4 (T) - Body ground	Ignition switch ON, combination switch position TAIL or HEAD	10 to 14 V

   Fig 5: Disconnecting R6 Rheostat Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Measure the resistance of the wire harness side connector.

   Standard resistance 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Specified Condition
   R6-5 (E) - Body ground	Below 1 Ω

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK : REPLACE LIGHT CONTROL RHEOSTAT