Lighting System - Headlight Signal Circuit
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
PERFORM ACTIVE TEST USING INTELLIGENT TESTER (HEADLIGHT)
INSPECT HEADLIGHT RELAY (HEAD LO)
CHECK HARNESS AND CONNECTOR (BATTERY - HEADLIGHT RELAY [HEAD LO])
CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [HEAD LO] - MAIN BODY ECU [COWL SIDE JUNCTION BLOCK LH])
LIGHTING SYSTEM - Headlight Signal Circuit
DESCRIPTION
The main body ECU receives a headlight low switch information signal from the light control switch, and illuminates the headlight low beam.
WIRING DIAGRAM
INSPECTION PROCEDURE
- Inspect the fuses and bulbs for circuits related to this system before performing the following inspection procedure.
| 1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (HEADLIGHT) |
Using the intelligent tester, perform the Active Test ().
Main Body| Tester Display | Test Part | Control Range | Diagnostic Note |
| Headlight Relay | Headlight | ON or OFF | - |
- OK:
- Headlight low beam turns on/turns off.
| OK | |
| |
| REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) |
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| 2.INSPECT HEADLIGHT RELAY (HEAD LO) |
Remove the headlight relay from the engine room relay block, junction block.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
| Tester Connection | Condition | Specified Condition |
| 3 - 5 | Battery voltage not applied to terminals 1 and 2 | 10 kΩ or higher |
| Battery voltage applied to terminals 1 and 2 | Below 1 Ω |
| | REPLACE HEADLIGHT RELAY (HEAD LO) |
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| 3.CHECK HARNESS AND CONNECTOR (BATTERY - HEADLIGHT RELAY [HEAD LO]) |
Remove the headlight relay from the engine room relay block, junction block.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
| Tester Connection | Condition | Specified Condition |
| Headlight relay terminal 1 - Body ground | Always | 11 to 14 V |
| Headlight relay terminal 5 - Body ground |
Text in Illustration| *a | Front view of wire harness connector
(to Headlight Relay [HEAD LO]) |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 4.CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [HEAD LO] - MAIN BODY ECU [COWL SIDE JUNCTION BLOCK LH]) |
Remove the headlight relay from the engine room relay block, junction block.
Disconnect the 2B main body ECU connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
| Tester Connection | Condition | Specified Condition |
| Headlight relay terminal 2 - 2B-18 | Always | Below 1 Ω |
| Headlight relay terminal 2 - Body ground | Always | 10 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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| OK | |
| |
| PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE ()
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