Last Modified: 05-13-2024 |
6.11:8.1.0 |
Doc ID: RM1000000025R3I |
Model Year Start: 2023 |
Model: GR Corolla |
Prod Date Range: [09/2022 - 11/2022] |
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (except TMC Made, and Gasoline Model, with Manual Air Conditioning System for Electrical Control Type): B14B2; Lost Communication with Front Panel LIN; 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022] |
DTC
|
B14B2
|
Lost Communication with Front Panel LIN
|
DESCRIPTION
The air conditioning control 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 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 assembly
|
-
Air conditioning control assembly
-
Harness or connector
-
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 ASSEMBLY - IG POWER SOURCE AND BODY GROUND)
|
(a) Disconnect the I37 air conditioning control assembly connector.
(b) Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Condition
|
Specified Condition
|
I37-9 (IG+) - Body ground
|
Ignition switch ON
|
11 to 14 V
|
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
I37-13 (GND) - Body ground
|
Always
|
Below 1 Ω
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
2.
|
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)
|
(a) Disconnect the I49 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
|
I37-7 (LIN1) - I49-7 (LIN1)
|
Always
|
Below 1 Ω
|
I37-7 (LIN1) or I49-7 (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 I49 air conditioning amplifier assembly connector.
(b) Turn the ignition switch to ON.
(c) Using an oscilloscope, check the waveform.
OK:
Waveform is similar to that shown in the illustration.
Item
|
Content
|
Terminal No.
|
I49-7 (LIN1) - Body ground
|
Tool Setting
|
2 V/DIV., 20 ms./DIV.
|
Condition
|
Ignition switch ON
|
|