Last Modified: 08-21-2023 |
6.11:8.1.0 |
Doc ID: RM100000001A3OK |
Model Year Start: 2019 |
Model: Avalon HV |
Prod Date Range: [04/2018 -
] |
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): B14B2; Lost Communication with Front Panel LIN; 2019 - 2022 MY Avalon HV [04/2018 - ] |
DTC
|
B14B2
|
Lost Communication with Front Panel LIN
|
DESCRIPTION
The air conditioning control panel (radio and display receiver assembly) communicates with the air conditioning amplifier assembly via LIN communication.
If a malfunction occurs in the LIN communication system, the air conditioning amplifier assembly will not operate, even if the air conditioning control panel (radio and display receiver assembly) is operated.
DTC No.
|
Detection Item
|
DTC Detection Condition
|
Trouble Area
|
Memory
|
B14B2
|
Lost Communication with Front Panel LIN
|
Lost communication with air conditioning control panel (radio and display receiver assembly)
|
-
Harness or connector
-
Air conditioning control panel (radio and display receiver assembly)
-
Air conditioning amplifier assembly
|
Memorized
(10 sec. or more)*
|
-
*: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
1.
|
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL PANEL (RADIO AND DISPLAY RECEIVER ASSEMBLY) - POWER SOURCE AND BODY GROUND)
|
(a) Disconnect the G20 air conditioning control panel (radio and display receiver assembly) connector.
(b) Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Condition
|
Specified Condition
|
G20-3 (+B) - Body ground
|
Power switch off
|
11 to 14 V
|
G20-2 (IG+) - Body ground
|
Power switch on (IG)
|
11 to 14 V
|
G20-10 (ACC) - Body ground
|
Power switch on (ACC)
|
11 to 14 V
|
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
G20-6 (GND) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
2.
|
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL PANEL (RADIO AND DISPLAY RECEIVER ASSEMBLY) - AIR CONDITIONING AMPLIFIER ASSEMBLY)
|
(a) Disconnect the G35 air conditioning amplifier assembly connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
G20-8 (LIN1) - G35-14 (LIN1)
|
Always
|
Below 1 Ω
|
G20-8 (LIN1) or G35-14 (LIN1) - Other terminals and body ground
|
Always
|
10 kΩ or higher
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
3.
|
INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY
|
(a) Connect the G35 air conditioning amplifier assembly connector.
(b) Turn the power switch on (IG).
(c) Using an oscilloscope, check the waveform.
Item
|
Content
|
Terminal No.
|
G35-14 (LIN1) - Body ground
|
Tool Setting
|
2 V/DIV., 20 ms./DIV.
|
Condition
|
Power switch on (IG)
|
OK:
Waveform is similar to that shown in the illustration.
OK
|
|
|
4.
|
INSPECT AIR CONDITIONING CONTROL PANEL (RADIO AND DISPLAY RECEIVER ASSEMBLY)
|
*a
|
Component with harness connected
(Air Conditioning Control Panel (Radio and Display Receiver Assembly))
|
(a) Connect the G20 air conditioning control panel (radio and display receiver assembly) connector.
(b) Turn the power switch on (IG).
(c) Using an oscilloscope, check the waveform.
Item
|
Content
|
Terminal No.
|
G20-8 (LIN1) - Body ground
|
Tool Setting
|
2 V/DIV., 20 ms./DIV.
|
Condition
|
Power switch on (IG)
|
OK:
Waveform is similar to that shown in the illustration.
|