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 |
---|---|---|---|---|
B14B287 |
Lost Communication with Front Panel LIN Missing Message |
Diagnosis Condition:
Malfunction Status:
Detection Time:
|
| Memorized |
Vehicle Condition | |||
---|---|---|---|
Pattern 1 | Pattern 2 | ||
Diagnosis Condition | Ignition switch ON |
○ | ○ |
Malfunction | Error communication with air conditioning control assembly |
○ | - |
Lost communication with air conditioning control assembly |
- | ○ | |
Detection Time | Continuously for 10 seconds or more |
Continuously for 10 seconds or more | |
Trip Count | 1 trip |
1 trip |
HINT:
If the conditions of either of these patterns are detected, a DTC will be stored.
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) |
(a) Disconnect the I37 air conditioning control assembly connector. |
|
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Switch Condition |
Specified Condition |
---|---|---|
I37-9 (IG+) - Body ground |
Ignition switch ON | 11 to 14 V |
NG | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
2. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - BODY GROUND) |
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition |
Specified Condition |
---|---|---|
I37-13 (GND) - Body ground |
Always | Below 1 Ω |
NG | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
3. |
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 |
|
4. |
INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY |
(a) Connect the I49 air conditioning amplifier assembly connector.
(b) Using an oscilloscope, check the waveform.
OK: Waveform is similar to that shown in the illustration. |
|
NG | REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
|
5. |
INSPECT AIR CONDITIONING CONTROL ASSEMBLY |
(a) Connect the air conditioning control assembly connector. |
|
(b) Using an oscilloscope, check the waveform.
Item | Content |
---|---|
Terminal No. | I37-7 (LIN1) - Body ground |
Tool Setting | 2 V/DIV., 20 ms./DIV. |
Condition | Ignition switch ON |
OK:
Waveform is similar to that shown in the illustration.
OK | REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
NG | REPLACE AIR CONDITIONING CONTROL ASSEMBLY |