Light Control Switch Circuit: Procedure

1. Inspect the headlight dimmer switch assembly. Refer to INSPECTION .

   OK

   Headlight dimmer switch assembly is normal.

NG → See step   4 

OK: Go to next step 

1. Disconnect the E12 headlight dimmer switch assembly connector.
2. Disconnect the E42 daytime running light relay connector.
   Fig 1: Checking Harness And E12 & E42 Connector (Switch - Daytime Running Light Relay)

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E12-11 (HU) - E42-16 (HI)	Always	Below 1 Ω
   E12-17 (HF) - E42-8 (HF)	Always	Below 1 Ω
   E12-18 (T) - E42-15 (T)	Always	Below 1 Ω
   E12-20 (H) - E42-5 (H)	Always	Below 1 Ω
   E12-11 (HU) - Body ground	Always	10 kΩ or higher
   E12-17 (HF) - Body ground	Always	10 kΩ or higher
   E12-18 (T) - Body ground	Always	10 kΩ or higher
   E12-20 (H) - Body ground	Always	10 kΩ or higher
   E12-12 (EL) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   3