Headlight Beam Level Control ECU Communication Circuit

LIGHTING SYSTEM: Headlight Beam Level Control ECU Communication Circuit

Headlight Beam Level Control ECU Communication Circuit

DESCRIPTION

Multiplex network body ECU sends signals that the headlight is ON and the daytime running light is on to the headlight beam level control ECU and operates the headlight beam level control system.
Headlight beam level control ECU receives the vehicle speed signal from the skid control ECU, and engine condition from the generator assembly.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT HEADLIGHT BEAM LEVEL CONTROL ECU





(a) Measure the voltage according to the value(s) in the table below.
Voltage:






NG -- CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL J/B - HEADLIGHT BEAM LEVEL CONTROL ECU)
OK -- Continue to next step.
2. INSPECT HEADLIGHT BEAM LEVEL CONTROL ECU





(a) Measure the voltage according to the value(s) in the table below.
Voltage:










(b) *1: Oscilloscope wave
HINT:
- Gauge set: 5 V/DIV. 2 ms/DIV
- Condition: Drive at about 30 km/h (19 mph)

NG -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - HEADLIGHT BEAM LEVEL CONTROL ECU)
OK -- Continue to next step.
3. INSPECT HEADLIGHT BEAM LEVEL CONTROL ECU





(a) Measure the voltage according to the value(s) in the table below.
Voltage:






NG -- CHECK HARNESS AND CONNECTOR (GENERATOR ASSEMBLY - HEADLIGHT BEAM LEVEL CONTROL ECU)
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
4. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL J/B - HEADLIGHT BEAM LEVEL CONTROL ECU)





(a) Disconnect the 1D connector of instrument panel junction block assembly and the H17 connector of headlight beam level control ECU.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:










NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- GO TO FLOW CHART (HEADLIGHT RELAY CIRCUIT)
5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - HEADLIGHT BEAM LEVEL CONTROL ECU)





(a) Disconnect the S1 connector of skid control ECU and the H17 connector of headlight beam level control ECU.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- GO TO FLOW CHART OR PROBLEM SYMPTOMS TABLE
6. CHECK HARNESS AND CONNECTOR (GENERATOR ASSEMBLY - HEADLIGHT BEAM LEVEL CONTROL ECU)





(a) Disconnect the G2 connector generator and the H17 connector of headlight beam level control ECU.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPAIR OR REPLACE GENERATOR ASSEMBLY