1. Install the manifold gauge.
2. Verify the high-pressure side reading of the manifold gauge.
3. Measure the terminal voltage at PCM terminals 2BB, 2AX and 2AJ
4. Using the graph below, measure and verify the terminal voltage at 2AX.
5. Follow the PCM inspection when measuring the other terminal voltages..
Terminal 2BB: Approx. 5 V (Ignition switch on)
Terminal 2AJ: 1.0 V or less
If the each voltage is not normal, inspect the related wiring harness.
If there is any malfunction, replace the related wiring harness.
If wiring harness is normal, replace the refrigerant pressure sensor.

Refrigerant Pressure Sensor Inspection [Full Auto Air Conditioner]
Refrigerant Pressure Sensor Removal/Installation [Full Auto Air Conditioner]DSC HU/CM Inspection
1. Disconnect the DSC HU/CM connector..
2. Connect the negative battery cable..
3. Attach the tester lead to the DSC HU/CM wiring harness-side connector and
inspect voltage, continuity, or resistance according to the standard (reference)
on the table.
Standard (Reference)
...
A/C Compressor Control [Full Auto Air Conditioner]
Purpose
The A/C compressor control switches the A/C compressor on/off according to
the vehicle environment.
Function
The A/C compressor control turns the A/C compressor on/off based on the climate
control unit operation and signals from each sensor.
The A/C compress ...
Break-In Period
No special break-in is necessary, but a few precautions in the first 1,000 km
(600 miles) may add to the performance, economy, and life of your Mazda.
• Do not race the engine.
• Do not maintain one constant speed,
either slow or fast, for a long period of time.
• Do not drive constantl ...