Clock Display Circuit

OTHER SYSTEM: CLOCK: Clock Display Circuit
- Clock Display Circuit

DESCRIPTION

The clock assembly uses this circuit to communicate with the A/C amplifier via the direct line. The clock assembly uses this circuit to receive auto dimmer signals. When the clock assembly receives an auto dimmer signal from the main body ECU through the A/C amplifier via the direct line, the clock assembly causes the clock display to be dimmed.

HINT
If the automatic light control sensor has a malfunction, DTC B1244 is output.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check if CAN communication DTC is output Diagnosis System.

Result:





B -- GO TO CAN COMMUNICATION SYSTEM
A -- Continue to next step.

2. CHECK AIR CONDITIONING SYSTEM

(a) Check the the heater control panel illumination.

OK:

The heater control panel illumination operates normally.

NG -- GO TO AIR CONDITIONING SYSTEM
OK -- Continue to next step.

3. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect Techstream to the DLC3.

(b) Engine switch on (IG).

(c) Turn the tester ON.

(d) Light control switch TAIL or HEAD.

(e) Enter the following menus: Body Electrical / Main Body / Active Test.

(f) Check the clock illumination.

Main Body:





OK:

The clock illumination is dimmed when the dimmer signal is ON.

HINT
Refer to the sensitivity setting in the customization table of the automatic light control system Customize Parameters.

NG -- CHECK HARNESS AND CONNECTOR (ILL+)

OK -- REPLACE MAIN BODY ECU

4. CHECK HARNESS AND CONNECTOR (ILL+)

(a) Disconnect the E3 (*1)/E18 (*2) connector.





(b) Measure the voltage according to the value(s) in the table below.

Standard voltage:





*1: w/ Navigation System w/o Multi-display

*2: w/ Navigation System

*3: w/ Navigation System w/ Multi-display

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (CLOCK ASSEMBLY - COMBINATION METER)

(a) Disconnect the E19 connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:





*1: w/o Navigation System w/o Multi-display

*2: w/ Navigation System

*3: w/o Navigation System w/ Multi-display

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. INSPECT CLOCK ASSEMBLY

(a) Reconnect the E19 connector.





(b) Check the waveform shown in the illustration below.

OK:





(1) Waveform (Reference): Using oscilloscope:









HINT
Duty ratio changes as the illumination becomes darker (the period "A" shown in the illustration becomes longer).

Result:





HINT
The whole heater control panel/multi-display should be replaced if the clock assembly has a malfunction because this part is not independently supplied.

A -- REPLACE HEATER CONTROL PANEL

B -- REPLACE MULTI-DISPLAY

C -- REPLACE COMBINATION METER ASSEMBLY