DESCRIPTION
The radio receiver assembly uses this circuit to communicate with the main body ECU (multiplex network body ECU) via a direct line. The main body ECU (multiplex network body ECU) uses this circuit to send an auto dimmer signal to the radio receiver assembly. The main body ECU (multiplex network body ECU) detects the position of the light control switch according to the resistance. When the light control switch is set to the head or tail position, the resistance between the head or tail terminal and body ground is below 1Ω. When the light control switch is set to the head or tail position, the main body ECU (multiplex network body ECU) sends an auto dimmer signal to the radio receiver assembly. When the radio receiver assembly receives an auto dimmer signal from the main body ECU (multiplex network body ECU), the radio receiver assembly causes the instrument panel illumination to be dimmed.
WIRING DIAGRAM
INSPECTION PROCEDURE
Note
If the main body ECU (multiplex network body ECU) is replaced, refer to Service Bulletin.
PROCEDURE
CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
Disconnect the H83 radio receiver assembly connector.
Measure the voltage according to the value(s) in the table below.
Standard Voltage | ||||||
---|---|---|---|---|---|---|
|
NG |
CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) Click here |
OK |
REPLACE RADIO RECEIVER ASSEMBLY Click here
CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
Disconnect the H83 radio receiver assembly connector.
Disconnect the 3B instrument panel junction block assembly connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | |||||||||
---|---|---|---|---|---|---|---|---|---|
|
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
OK |
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
Remove the instrument panel junction block assembly Click here.
Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||
---|---|---|---|---|---|---|
|
*a | Component without harness connected (Instrument Panel Junction Block Assembly) |
- | - |
NG |
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here |
OK |
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here