Operation CHARM: Car repair manuals for everyone.
Home >> Mazda >> 2000 >> MX-5 Miata L4-1.8L DOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> A/C Signal >> Testing and Inspection
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A/C Signal: Testing and Inspection

1. Start the engine.
2. Turn the A/C switch and fan switch on.

3. Verify that the A/C compressor magnetic clutch actuates.
- If is does not actuate, go to symptom troubleshooting No.23 A/C does not work.

4. Fully open the throttle valve and verify that the A/C compressor magnetic clutch does not actuate for 3 - 6 seconds.
- If it actuates, proceed Step 5.




5. Connect the SSTs (NGS tester) to DLC-2.
6. Turn the A/C switch off.
7. Turn the ignition switch to ON.
8. Select SIMULATION TEST and press TRIGGER.
9. Select IG ON TEST and press TRIGGER.
10. Select A/C RLY and press TRIGGER.
11. Press START.

12. Turn the A/C relay from off to on and inspect if the operation sound of the relay is heard.
- If the operation sound is heard, inspect TP V PID.
- If the operation sound is not heard, inspect the following.
- A/C relay
- Open or short to ground circuit in wiring harness and connectors (Main relay - A/C relay - PCM terminal 1S.)
- A/C related parts
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