LIGHTING SYSTEM Instrument Panel Illumination Circuit

DESCRIPTION

• When the taillights are turned on by the automatic light control or manual light control, the instrument panel illumination is also turned on.

• When the taillights are turned on by the daytime running light control, the instrument panel illumination ON is prohibited.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER

   
   

   1. Connect the intelligent tester tester to the DLC3.

   2. Turn power switch on (IG).

   3. Turn the intelligent tester tester on.

   4. Enter the following menus: Body / Main Body / Active Test.

   5. Check that the relay operate.

      Main Body

      Tester Display	Test Part	Control Range	Diagnostic Note
      Interior Panel Relay	Interior panel relay	ON/OFF	Power switch is off and light control switch in tail position.

      OK
      Relay operates (each light comes on or off).

   
   

   NG

   INSPECT INSTRUMENT PANEL ILLUMINATION RELAY (PANEL) Click here

   OK

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

2. INSPECT INSTRUMENT PANEL ILLUMINATION RELAY (PANEL)

   
   

   1. 

      Remove the PANEL relay.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition 3 - 5 Voltage is not applied between terminals 1 and 2 10 kΩ or higher 3 - 5 Voltage is applied between terminals 1 and 2 Below 1 Ω

   
   

   NG

   REPLACE INSTRUMENT PANEL ILLUMINATION RELAY

   OK

3. CHECK HARNESS AND CONNECTOR (BATTERY - PANEL RELAY)

   
   

   1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition Relay terminal 1 - Body ground Light control switch off → tail Below 1 V → 11 to 14 V Relay terminal 3 - Body ground Light control switch off → tail Below 1 V → 11 to 14 V

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (PANEL RELAY - MAIN BODY ECU)

   
   

   1. Disconnect the L7 main body ECU (multiplex network body ECU) connector.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Relay terminal 2 - L7-15 (PANL) Always Below 1 Ω L7-15 (PANL) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

5. INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

   
   
   1. 

      Text in Illustration

      *1	Component with harness connected (Main Body ECU (Multiplex Network Body ECU))

      Reconnect the L7 main body ECU (multiplex network body ECU) connector.

   2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition L7-15 (PANL) - Body ground Light control switch in tail Below 1 V Light control switch in AUTO and taillights are on Below 1 V Taillights are turned on by the daytime running light control 11 to 14 V

   
   

   NG

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   OK

   REPAIR OR REPLACE HARNESS OR CONNECTOR (RELAY - EACH INSTRUMENT PANEL ILLUMINATION)