Suzuki SX4 Service Manual page 187

Step
1 Was "Engine and Emission Control System Check"
performed?
2 A/C refrigerant pressure sensor power supply circuit
check
1) Disconnect connector from A/C refrigerant pressure
sensor with ignition switch turned OFF.
2) Check for proper connection of A/C refrigerant pressure
sensor at "GRY/RED", "RED/BLU" and "ORN" wire
terminals.
3) Turn ON ignition switch, measure voltage between
engine ground and "GRY/RED" wire terminal of A/C
refrigerant pressure sensor connector.
Is voltage 4 – 6 V?
3 A/C refrigerant pressure sensor power supply circuit
check
1) Disconnect connectors from MAP sensor with ignition
switch turned OFF.
2) Turn ON ignition switch, measure voltage between
engine ground and "GRY/RED" wire terminal of A/C
refrigerant pressure sensor connector.
Is voltage 4 – 6 V?
4 A/C refrigerant pressure sensor power supply circuit
check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between engine ground and "C01-
14" terminal of ECM connector.
Is resistance infinity?
5 A/C refrigerant pressure sensor signal circuit check
1) Connect connectors to ECM.
2) Turn ON ignition switch, measure voltage between
engine ground and "RED/BLU" wire terminal of A/C
refrigerant pressure sensor connector.
Is voltage 4 – 6 V?
6 A/C refrigerant pressure sensor signal circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between engine ground and "E01-
55" terminal of ECM connector.
Is resistance infinity?
7 A/C refrigerant pressure sensor check
1) Check A/C refrigerant pressure sensor referring to "A/C
Refrigerant Pressure Sensor and Its Circuit Inspection:
Manual Type in Section 7B" or "A/C Refrigerant
Pressure Sensor and Its Circuit Inspection: Automatic
Type in Section 7B".
Is it in good condition?
Action
Engine General Information and Diagnosis:
Yes
Go to Step 2.
Go to Step 5.
Faulty MAP sensor.
Go to Step 6.
Go to Step 7.
Go to Step 7.
Substitute a known-
good ECM and recheck.
1A-137
No
Go to "Engine and
Emission Control
System Check".
Go to Step 3.
Go to Step 4.
"GRY/RED" wire is
shorted to ground
circuit.
Go to Step 6.
"RED/BLU" wire is
shorted to ground
circuit.
Faulty A/C refrigerant
pressure sensor.