Vehicle Speed Signal Circuit

LIGHTING: LIGHTING SYSTEM: Vehicle Speed Signal Circuit

Vehicle Speed Signal Circuit

DESCRIPTION

Headlight beam level control ECU receives the vehicle speed signal from the combination meter.

WIRING DIAGRAM





INSPECTION PROCEDURE
HINT: Check if the combination meter operation is normal before performing the following procedure.

PROCEDURE

1. CHECK HEADLIGHT BEAM LEVEL CONTROL ECU (SPEED VOLTAGE)




(a) Measure the voltage of the wire harness side connector.
Standard voltage:






OK:
Waveform is output as shown in the illustration.
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG -- Continue to next step.

2. CHECK WIRE HARNESS (ECU - METER)




(a) Disconnect the H12 ECU connector.
(b) Disconnect the C10 meter connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- REPLACE COMBINATION METER