Communication Malfunction (Bus Ic) (B1497)
The air conditioning harness assembly connects the No. 1 air conditioning amplifier assembly and each servo motor. The No. 1 air conditioning amplifier assembly supplies power and sends operation instructions to each servo motor through the No. 1 air conditioning amplifier assembly. Each servo motor sends the damper position information to the No. 1 air conditioning amplifier assembly.
DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
B1497 |
An open circuit or malfunction in the communication line. |
|
PROCEDURE
CHECK NO. 1 AIR CONDITIONING AMPLIFIER ASSEMBLY
(a) Remove the No. 1 air conditioning amplifier assembly with its connectors still connected (See page |
 |
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).(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
|---|---|---|
z15-2 (BUS G) - Body ground |
Always |
Below 1 Ω |
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
z15-2 (BUS G) - z15-4 (B BUS) |
Always |
11 to 14 V |
z15-2 (BUS G) - z15-3 (BUS) |
Ignition switch ON |
Pulse generation |
*a |
Component with harness connected (No. 1 Air Conditioning Amplifier Assembly) |
Result | Proceed to |
|---|---|
OK (When troubleshooting according to problem symptoms table) |
A |
OK (When troubleshooting according to the DTC) |
B |
NG |
C |
| A | .gif) | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| B | | REPLACE AIR CONDITIONING HARNESS ASSEMBLY |
| C | | REPLACE NO. 1 AIR CONDITIONING AMPLIFIER ASSEMBLY |
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