Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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Link: lemon-manuals.la or lemon-manuals.org.ua

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A/C Signal: Testing and Inspection

A/C Cut Control Inspection
1. Start the engine.
2. Turn the A/C switch and fan switch to ON.
3. Verify that the A/C compressor magnet clutch actuates.
4. If is does not actuate, go to troubleshooting of the A/C.
5. Fully open the throttle valve and verify that the A/C compressor magnet clutch does not actuate for 3-6 seconds.
6. If it actuates, check the following.




a. Connect the Special Service Tools to the data link connector-2.
b. Turn the A/C switch to OFF.
c. Turn the ignition switch to ON.




d. Select the SIMULATION TEST function on the NGS display.
e. Turn the A/C relay from OFF to ON by using the "A/C RLY" and check for the operation sound of the relay.
- If the operation sound is heard, check the following:
- ECM terminal voltage
- Load/no load judgement signal
- Throttle position sensor TVO signal
- If the operation sound is not heard, check the following:
- A/C relay
-Open circuit in Wiring harnesses and connectors (Main relay - A/C relay - ECM)