DESCRIPTION
When the A/C compressor is on, the A/C amplifier sends the A/C signal to the ECM, then ECM increases the fuel injection volume to improve driveability during engine idling.
WIRING DIAGRAM
INSPECTION PROCEDURE
When using intelligent tester:
PROCEDURE
READ VALUE USING INTELLIGENT TESTER (AIR CONDITIONER SIGNAL)
Connect the intelligent tester to the DLC3.
Start the engine.
Air conditioning switch on.
Select the item "Powertrain/Engine and ECT/Data List/A/C Signal" and read its value displayed on the intelligent tester.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| NG : |
|
INSPECT ECM (CHECK VOLTAGE) Click here |
| OK :PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE |
|
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
INSPECT ECM (CHECK VOLTAGE)
Start the engine.
Measure the voltage according to the value(s) in the table below.
| Standard voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| NG : |
|
CHECK HARNESS AND CONNECTOR (ECM - AIR CONDITIONER AMPLIFIER) Click here |
| OK :REPLACE ECM |
|
REPLACE ECM
CHECK HARNESS AND CONNECTOR (ECM - AIR CONDITIONER AMPLIFIER)
Disconnect the A/C amplifier H19 connector.
Disconnect the ECM B8 connector.
Measure the resistance according to the value(s) in the table below.
| Standard resistance (Check for open) | ||||
|---|---|---|---|---|
|
| Standard resistance (Check for short) | ||||
|---|---|---|---|---|
|
Tech Tips
*1: Terminal arrangement Click here.
| NG :REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK :REPLACE AIR CONDITIONER AMPLIFIER |
|
REPLACE AIR CONDITIONER AMPLIFIER
When not using intelligent tester:
PROCEDURE
INSPECT ECM (CHECK VOLTAGE)
Start the engine.
Measure the voltage according to the value(s) in the table below.
| Standard voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| NG : |
|
CHECK HARNESS AND CONNECTOR (ECM - AIR CONDITIONER AMPLIFIER) Click here |
| OK :PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE |
|
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
CHECK HARNESS AND CONNECTOR (ECM - AIR CONDITIONER AMPLIFIER)
Disconnect the A/C amplifier H19 connector.
Disconnect the ECM B8 connector.
Measure the resistance according to the value(s) in the table below.
| Standard resistance (Check for open) | ||||
|---|---|---|---|---|
|
| Standard resistance (Check for short) | ||||
|---|---|---|---|---|
|
Tech Tips
*1: Terminal arrangement Click here.
| NG :REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK :REPLACE AIR CONDITIONER AMPLIFIER |
|
REPLACE AIR CONDITIONER AMPLIFIER