Headlight Signal Circuit: Procedure
- READ VALUE USING TECHSTREAM
- Connect the Techstream to the DLC3.
- Turn the power switch on (IG).
- Turn the Techstream on.
- Enter the following menus: Body Electrical / HL Auto Leveling / Data List.
- Read the display on the Techstream.HL AUTO LEVELING
Tester Display Measurement Item/Range Normal Condition Diagnostic Note Lo Beam St Low beam headlight state/ON or OFF ON: Low beam headlights on
OFF: Low beam headlights off- OK
Normal conditions listed above are displayed.
NG → See step 2
OK → See step 3
- CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - HEADLIGHT LEVELING ECU ASSEMBLY)
- Disconnect the A48 headlight leveling ECU assembly connector.
- Disconnect the 1G No. 1 integration relay connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A48-3 (HDLP) - 1G-11 (HL4B) Always Below 1Ω A48-3 (HDLP) - Body ground Always 10 kΩ or higher
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK → See step 4
- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE
- REPLACE HEADLIGHT LEVELING ECU ASSEMBLY. Refer to REMOVAL