DESCRIPTION
The radio receiver assembly (A/C control panel) switch signals are sent to the air conditioning amplifier assembly via CAN communication.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
1. | CHECK CAN COMMUNICATION SYSTEM |
(a) Using the Techstream, check if the CAN communication system is functioning normally.
Click here
Result | Proceed to |
---|---|
CAN communication system DTCs are not output | A |
CAN communication system DTCs are output | B |
B | ![]() | GO TO CAN COMMUNICATION SYSTEM |
|
2. | CHECK AVC-LAN COMMUNICATION CIRCUIT |
(a) Check for an open or short in all AVC-LAN communication circuits.
w/ Navigation System: Click here
w/ Audio and Visual System (for 12.3 Inch Display): Click here
w/ Audio and Visual System (for 8 Inch Display): Click here
OK:
There is no open or short circuit.
NG | ![]() | REPAIR AVC-LAN COMMUNICATION CIRCUIT |
|
3. | CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY (A/C CONTROL PANEL) - POWER SOURCE AND BODY GROUND) |
(a) Disconnect the J148 and J149 radio receiver assembly (A/C control panel) connectors.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
J149-19 (IG) - Body ground | Engine switch on (IG) | 11 to 14 V |
J148-15 (ACC1) - Body ground | Engine switch on (ACC) | 11 to 14 V |
J148-4 (+B1) - Body ground | Always | 11 to 14 V |
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J148-1 (GND1) - Body ground | Always | Below 1 Ω |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
4. | CHECK HARNESS AND CONNECTOR (MULTI-DISPLAY ASSEMBLY - POWER SOURCE AND BODY GROUND) |
(a) Disconnect the J56 multi-display assembly connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
J56-24 (ACC) - Body ground | Engine switch on (ACC) | 11 to 14 V |
J56-12 (B) - Body ground | Always | 11 to 14 V |
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J56-13 (GND1) - Body ground | Always | Below 1 Ω |
OK | ![]() | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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