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Inspection Procedure 10

A/C Compressor Clutch Power supply system

A/C Compressor Power Supply Circuit Part 1:




A/C Compressor Power Supply Circuit Part 2:






TECHNICAL DESCRIPTION (COMMENT)
If cool air is not distributed when the A/C switch is on, the air thermo sensor or the A/C compressor clutch relay system may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the A/C compressor clutch relay
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Test Harness Set




STEP 1. Check A/C compressor clutch relay connector B-13X for damage.

Q: Is A/C compressor clutch relay connector B-13X in good condition?

YES : Go to Step 2.

NO : Repair or replace the connector. Refer to Harness Connector Inspection. Check that the air conditioning works normally.







STEP 2. Check the A/C compressor clutch relay continuity.
Follow the table to check the A/C compressor clutch relay for continuity.

Q: Is the A/C compressor clutch relay in good condition?

YES : Go to Step 3.

NO : Replace the A/C compressor clutch relay. Check that the air conditioning works normally.

STEP 3. Measure the voltage at A/C compressor clutch relay connector B-13X.




1. Disconnect A/C compressor connector B-13X and measure the voltage at the relay box side.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal 2 and ground.
- The measured value should be approximately 12 volts (battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES : Go to Step 5.

NO : Go to Step 4.













STEP 4. Check the wiring harness between A/C compressor clutch relay connector B-13X (terminal 2) and the ignition switch (IG2).

NOTE: Also check intermediate connector C-116, joint connector (2) C-01, junction block connectors C-211 and C-212. If intermediate connector C-116, joint connector (2) C-01, or junction block connectors C-211 or C-212 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q: Is the wiring harness between A/C compressor clutch relay connector B-13X (terminal 2) and the ignition switch (IG2) in good condition?

YES : Check that the air conditioning works normally.

NO : Repair the wiring harness. Check that the air conditioning works normally.

STEP 5. Measure the voltage at A/C compressor clutch relay connector B-13X.




1. Disconnect A/C compressor connector B-13X and measure the voltage at the relay box side.




2. Measure the voltage between terminal 1 and ground.
- The measured value should be approximately 12 volts (battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES : Go to Step 7.

NO : Go to Step 6.







STEP 6. Check the wiring harness between A/C compressor clutch relay connector B-13X (terminal 1) and the battery.

NOTE: Also check intermediate connector A-13. If intermediate connectors A-13 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q: Is the wiring harness between A/C compressor clutch relay connector B-13X (terminal 1) and the battery in good condition?

YES : Check that the air conditioning works normally.

NO : Repair the wiring harness. Check that the air conditioning works normally.




STEP 7. Check A/C compressor connector B-117 for damage.

Q: Is and A/C compressor connector B-117 in good condition?

YES : Go to Step 8.

NO : Repair or replace the connector. Refer to Harness Connector Inspection. Check that the air conditioning works normally.







STEP 8. Check the wiring harness between A/C compressor clutch relay connector B-13X (terminal 4) and A/C compressor connector B-117 (terminal 1).

Q: Is the wiring harness between A/C compressor clutch relay connector B-13X (terminal 4) and A/C compressor connector B-117 (terminal 1) in good condition?

YES : Go to Step 9.

NO : Repair the wiring harness. Check that the air conditioning works normally.




STEP 9. Check powertrain control module connector C-114 for damage.

Q: Is powertrain control module connector C-114 in good condition?

YES : Go to Step 10.

NO : Repair or replace the connector. Refer to Harness Connector Inspection. Check that the air conditioning works normally.







STEP 10. Check the wiring harness between powertrain control module connector C-114 (terminal 16) and A/C compressor clutch relay connector B-13X (terminal 3).

Q: Is the wiring harness between powertrain control module connector C-114 (terminal 16) and A/C compressor clutch relay connector B-13X (terminal 3) in good condition?

YES : Check that the air conditioning works normally.

NO : Repair the wiring harness. Check that the air conditioning works normally.