01 - Inspection Procedure
When the Ignition Switch is "ON," the A/C does not Operate.DIAGNOSIS
STEP 1. Check for refrigerant leaks.
Q: Is the refrigerant leaking?
YES: Repair the leak. Then go to Step 10.
NO: Go to Step 2.
STEP 2. Check for excessive refrigerant.
Q: Is the refrigerant in good condition?
YES: Go to Step 3.
NO: Use the refrigerant recovery station to remove all of the refrigerant, and then calculate the amount of the refrigerant and charge it. Then go to Step 10.
STEP 3. Check the A/C compressor relay continuity.
Q: Is the A/C compressor relay in good condition?
YES: Go to Step 4.
NO: Replace. Then go to Step 10.
STEP 4. Check the magnetic clutch operation.
Connect the battery (+) terminal to the compressor magnetic clutch connector terminal 3 and ground the battery (-) terminal to the body of the compressor.
Q: Can the sound of the magnetic clutch (click) be heard?
YES: Go to Step 5.
NO: Replace. Then go to Step 10.
STEP 5. Check the dual pressure switch operation.
1. Remove the dual pressure switch connector and connect the high/low pressure side terminals located on the harness side as shown in the illustration.
2. Install a gauge manifold to the high-pressure side service valve of the refrigerant line.
3. When the high/low pressure sides of the dual pressure switch are at operation pressure (ON) and the resistance is less than two ohms between the respective terminals, then the condition is normal. If open loop, replace the switch.
Q: Is the dual pressure switch operating properly?
YES: Go to Step 6.
NO: Replace the switch. Then go to Step 10.
STEP 6. Check the A/C switch continuity.
Q: Is there continuity at the A/C switch?
YES: Go to Step 7.
NO: Replace. Then go to Step 10.
STEP 7. Check the blower switch continuity.
Q: Is there continuity the blower switch?
YES: Go to Step 8.
NO: Replace. Then go to Step 10.
STEP 8. Measure the automatic compressor controller terminal voltage.
Q: Is the automatic compressor controller terminal voltage correct.
YES: Go to Step 9.
NO: Replace. Then go to Step 10.
STEP 9. Measure the powertrain control module terminal voltage.
Refer to Computers and Control Systems/Testing, Diagnosis - Check at the Powertrain Control Module (PCM).
Q: Is the terminal voltage correct?
YES: Go to Step 10.
NO: Replace. Then go to Step 10.
STEP 10. Check symptoms.
Q: Is the A/C operating properly?
YES: This diagnosis is complete. (If no malfunctions are not found in all steps, an intermittent malfunction is suspected. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.)
NO: Go to Step 1.