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Makes 🢒 Chevrolet 🢒 1998 🢒 Tahoe 4WD - RHD 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 HVAC Compressor Clutch Does Not Disengage

HVAC Compressor Clutch Does Not Disengage Gasoline

Step

Action

Value(s)

Yes

No

DEFINITION: Checking the mechanical action of the A/C compressor clutch

1
  1. Place the ignition switch in the LOCK position.
  2. Place the mode switch on the A/C controller in the OFF position.
  3. Verify that the compressor is seized.

Is the compressor seized?

--

Go to Step 2

Go to Step 3

2

Replace the A/C compressor.

Is the repair complete?

--

System OK

--

3
  1. Place the ignition switch in the RUN position.
  2. Disconnect connector C3 at the VCM.
  3. Connect an unpowered test lamp between VCM connector C3 cavity 25 and ground.

Does the test lamp light?

--

Go to Step 4

Go to Step 11

4
  1. Disconnect the connector at the A/C compressor high pressure cutoff switch.
  2. Connect an unpowered test lamp between the A/C compressor high pressure cutoff switch connector cavity B and ground.

Does the test lamp light?

--

Go to Step 5

Go to Step 8

5

Repair the short to voltage in CKT 762 (DK GRN/WHT) between the A/C compressor high pressure cutoff switch and the VCM.

Is the repair complete?

--

System OK

--

6
  1. Disconnect the connector at the A/C compressor cycling switch.
  2. Connect an unpowered test lamp between A/C compressor cycling switch connector cavity B and ground.

Does the test lamp light?

--

Go to Step 7

Go to Step 8

7

Repair the short to voltage on CKT 603 (DK GRN) between the A/C compressor cycling switch and the A/C compressor high pressure cutoff switch.

Is the repair complete?

--

System OK

--

8
  1. Disconnect connector C1 at the A/C controller.
  2. Connect an unpowered test lamp between the A/C controller connector C1 cavity A and ground.

Does the test lamp light?

--

Go to Step 9

Go to Step 10

9

Repair the short to voltage on CKT 66 (LT GRN) between the A/C controller and the A/C compressor high pressure cutoff switch.

Is the repair complete?

--

System OK

--

10

Replace the A/C controller.

Is the repair complete?

--

System OK

--

11
  1. Remove the A/C compressor clutch relay from the socket in the underhood fuse-relay center.
  2. Connect an unpowered test lamp between A/C compressor clutch connector cavity B and ground.

Does the test lamp light?

--

Go to Step 12

Go to Step 13

12

Repair the short to voltage in CKT 591 (DK GRN) between the underhood fuse-relay center and the A/C compressor clutch.

Is the repair complete?

--

System OK

--

13

Connect a self-powered test lamp between the A/C compressor clutch relay socket cavity B6 and ground.

Does the test lamp light?

--

Go to Step 15

Go to Step 14

14

Replace the A/C compressor clutch relay.

Is the repair complete?

--

System OK

--

15
  1. Disconnect connector C2 at the VCM.
  2. Connect a self-powered test lamp between A/C compressor clutch relay socket cavity B6 and ground.

Does the test lamp light?

--

Go to Step 16

Go to Step 17

16

Repair the short to ground in CKT 459 (DK GRN/WHT) between the underhood fuse-relay center and the VCM.

Is the repair complete?

--

System OK

--

17

Replace the VCM.

Is the repair complete?

--

System OK

--