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Makes 🢒 Chevrolet 🢒 1997 🢒 Corvette 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 HVAC Compressor Clutch Does Not Engage

A/C Compressor Clutch Does Not Engage <<C60>>

Step

Action

Value(s)

Yes

No

DEFINITION: A/C compressor clutch will not engage when an A/C request has been made and no Powertrain DTC are set.

1

Were you sent here from the HVAC Blower Controls System Check (C60)?

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Go to Step 2

Go to HVAC Blower Controls System Check (C60)

2
  1. Remove the A/C CLU Micro Relay #34.
  2. Disconnect the A/C compressor clutch connector.
  3. Using a DMM, measure for continuity between terminal A of the A/C compressor clutch connector and ground.

Is the resistance infinite?

--

Go to Step 4

Go to Step 3

3

Locate and repair a short to ground in CKT 59 between the underhood electrical center and the A/C compressor clutch connector.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

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4
  1. A/C CLU Micro Relay #34 still removed.
  2. A/C compressor clutch connector still disconnected.
  3. Connect a fused jumper between terminal 30 and terminal 87 of the underhood electrical center which is used for the A/C CLU Micro Relay #34.
  4. Using a DMM, measure the voltage at the A/C compressor clutch connector terminal A.

Is the voltage within the specified values?

10.0-14.0V

Go to Step 6

Go to Step 5

5

Locate and repair an open or a high resistance in CKT 59.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

--

6

Using a DMM, measure for continuity between terminal B of the A/C compressor clutch connector and ground.

Is the CKT 150 continuous to ground?

--

Go to Step 8

Go to Step 7

7

Locate and repair an open or a high resistance in CKT 150.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

--

8
  1. Disconnect the powertrain control module (PCM) connector C1.
  2. Reinstall the A/C CLU Micro Relay #34.
  3. Connect a fused jumper between the PCM connector C1 terminal 39 and ground.
  4. Turn the ignition switch to the ON position.
  5. Using a DMM, measure the voltage at the A/C compressor clutch connector terminal A.

Is the voltage within the specified values?

10.0-14.0V

Go to Step 9

Go to Step 10

9
  1. Remove the fused jumper from the PCM connector C1 terminal 39 and ground.
  2. Reconnect the A/C compressor clutch connector.
  3. Reinstall the fused jumper between the PCM connector C1 terminal 39 and ground.
  4. Turn the ignition switch to the ON position.

Does the A/C compressor clutch engage?

--

Go to System Performance Test

Go to Step 16

10
  1. Turn the ignition switch to the OFF position.
  2. Remove the A/C CLU Micro Relay #34.
  3. Using a DMM, measure for continuity between the PCM connector C1 terminal 39 and terminal 88 of the underhood electrical center which is used for the A/C CLU Micro Relay #34.

Is CKT 459 continuous between these two terminals?

--

Go to Step 12

Go to Step 11

11

Locate and repair an open or a high resistance in CKT 459.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

--

12

Replace the A/C CLU Mini Relay #34 and retest the A/C system.

Does replacing the A/C CLU Mini Relay #34 correct the concern?

--

Go to HVAC Blower Controls System Check (C60)

Go to Step 13

13
  1. Disconnect the HVAC control head connector C1.
  2. Connect a DMM between the PCM connector C1 terminal 47 and the HVAC control head connector C1 terminal B.
  3. Measure CKT 762 for continuity between these two connectors.

Is CKT 762 continuous?

--

Go to Step 15

Go to Step 14

14

Locate and repair an open or a high resistance in CKT 762.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

--

15
  1. Connect a DMM between the PCM connector C1 terminal 47 and ground.
  2. Measure CKT 762 for continuity to ground.

Is CKT 762 continuous to ground?

--

Go to Step 16

Go to Step 17

16

Locate and repair a short to ground in CKT 762.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

--

17
  1. Disconnect the DMM.
  2. Reconnect all connectors back to their respective modules.
  3. Install the scan tool to the diagnostic link connector.
  4. Start the engine and allow it to idle in Park.
  5. Select the area of the scan tool which will read HVAC button output status.
  6. Depress the A/C button on/off several times.

Does the scan tool read the A/C request being sent by the HVAC control head?

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Go to Step 18

Go to Step 19

18

Replace the PCM.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

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19

Replace the HVAC control head.

Is the repair complete?

--

Go to HVAC Blower Controls System Check (C60)

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