Headlight Dimmer Switch Circuit [02/2017 - 10/2017]: Procedure
WARNING: This page is about a different car, the 2019 Toyota C-HR and 2018 Toyota C-HR. However, it is still accessible from the selected car via links, so may be relevant.
- READ VALUE USING TECHSTREAM
- Connect the Techstream to the DLC3.
- Turn the ignition switch to ON.
- Turn the Techstream on.
- Enter the following menus: Body Electrical / Main Body / Data List.
- Read the Data List according to the display on the Techstream.
Body Electrical > Main Body > Data List
Tester Display Measurement Item Range Normal Condition Diagnostic Note Dimmer SW Dimmer switch high position signal ON or OFF ON: Dimmer switch in high or high flash position
OFF: Dimmer switch in low position- Passing Light SW Dimmer switch high flash position (pass) signal ON or OFF ON: Dimmer switch in high flash position
OFF: Dimmer switch not in high flash position- Auto Light SW Light control switch AUTO position signal ON or OFF ON: Light control switch in AUTO position
OFF: Light control switch not in AUTO position- Head Light SW (Head) Light control switch head position signal ON or OFF ON: Light control switch in head position
OFF: Light control switch not in head position- Head Light SW (Tail) Light control switch tail position signal ON or OFF ON: Light control switch in tail or head position
OFF: Light control switch not in tail or head position- Body Electrical > Main Body > Data List
Tester Display Dimmer SW Passing Light SW Auto Light SW Head Light SW (Head) Head Light SW (Tail) OK
Normal conditions listed above are displayed.
Result
Proceed to OK NG
Result:
OK
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE [02/2017 - 10/2017]
Result:
NG
See step 2
- INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY
HINT:
Inspect the items that did not change when reading the Data List.
- Remove the headlight dimmer switch assembly.
Refer to REMOVAL [02/2017 - 08/2020]
- Inspect the headlight dimmer switch assembly.
Refer to INSPECTION [02/2017 - 12/2021]
Result
Proceed to OK NG
Result:
NG
REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY. Refer to REMOVAL [02/2017 - 08/2020]
Result:
OK
See step 3
- Remove the headlight dimmer switch assembly.
- CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH ASSEMBLY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))
- Disconnect the F15 main body ECU (multiplex network body ECU) connector.
- Measure the resistance according to the value(s) in the chart below.
Standard Resistance
Tester Connection Condition Specified Condition F24-14 (HU) - F15-24 (HU) Always Below 1 Ω F24-17 (HF) - F15-10 (HF) Always Below 1 Ω F24-18 (T) - F15-22 (TAIL) Always Below 1 Ω F24-19 (H) - F15-12 (HEAD) Always Below 1 Ω F24-20 (A) - F15-8 (A) Always Below 1 Ω F24-14 (HU) or F15-24 (HU) - Body ground Always 10 kΩ or higher F24-17 (HF) or F15-10 (HF) - Body ground Always 10 kΩ or higher F24-18 (T) or F15-22 (TAIL) - Body ground Always 10 kΩ or higher F24-19 (H) or F15-12 (HEAD) - Body ground Always 10 kΩ or higher F24-20 (A) or F15-8 (A) - Body ground Always 10 kΩ or higher F24-15 (EL) - Body ground Always Below 1 Ω F24-8 (LFG) - Body ground Always Below 1 Ω Result
Proceed to OK NG
Result:
OK
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to REMOVAL [02/2017 - 10/2017]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR