GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Tracker - 2WD 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 HVAC Compressor Clutch Does Not Engage
Table 1: Compressor Control Module Voltage Table

Step

Action

Yes

No

1

Did you review the HVAC Compressor/Condenser Fan Circuit Description and perform the necessary inspections?

Go to Step 2

Go to Diagnostic Starting Point - HVAC Systems - Manual

2
  1. Start the engine.
  2. Turn the blower switch to any position except the OFF position.
  3. Turn the A/C switch to the ON position.

Does the A/C compressor clutch engage?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3
  1. Stop the engine.
  2. Disconnect the A/C compressor clutch connector.
  3. Turn the ignition switch to the ON position.
  4. Turn the blower switch to any position except the OFF position.
  5. Turn the A/C switch to the ON position.
  6. Test for battery voltage at the A/C compressor clutch connector.

Is battery voltage present?

Go to Step 4

Go to Step 5

4

Replace the A/C compressor clutch. Refer to Compressor Clutch Coil Replacement .

Is the repair complete?

Go to Step 37

--

5

Test for an open in the WHT/RED wire between the A/C compressor clutch relay and the A/C compressor clutch.

Is an open present?

Go to Step 36

Go to Step 6

6

Test for battery voltage at the A/C compressor clutch relay connector cavity 1.

Is battery voltage present?

Go to Step 8

Go to Step 7

7

Repair the open in the RED/BLK wire between the A/C compressor clutch relay and the A/C fuse or in the RED wire between the A/C fuse and the HTR fuse. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

8

Test for battery voltage at the A/C compressor clutch relay connector cavity 4.

Is battery voltage present?

Go to Step 10

Go to Step 9

9

Repair the open in the YEL/GRN wire between the A/C compressor clutch relay connector and the junction block. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

10
  1. Disconnect the A/C compressor clutch relay connector.
  2. Turn the ignition switch to the ON position.
  3. Turn the blower switch to any position except the OFF position.
  4. Turn the A/C switch to the ON position.
  5. Connect a test lamp between the A/C compressor clutch relay connector cavity 3 and B+.

Does the test lamp illuminate?

Go to Step 11

Go to Step 12

11

Replace the A/C compressor clutch relay. Refer to Compressor Relay Replacement .

Is the repair complete?

Go to Step 37

--

12

Test for an open in the PNK wire between the A/C compressor clutch relay cavity 3 and the A/C compressor control module.

Is an open present?

Go to Step 36

Go to Step 13

13

Test for an open in the BLK /YEL wire between G103 and the A/C compressor control module connector cavity 15.

Is an open present?

Go to Step 36

Go to Step 14

14

Test for battery voltage at the A/C compressor control module connector cavity 16 with a digital multimeter.

Is battery voltage present?

Go to Step 16

Go to Step 15

15

Repair the open in the BLK /WHT ignition feed wire between the IG fuse and the A/C compressor control module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

16
  1. Turn the ignition switch OFF.
  2. Disconnect the A/C refrigerant pressure switch connector.
  3. Test the A/C refrigerant pressure switch for continuity.
  4. Test the BLK wire between the A/C refrigerant pressure switch and G105 for continuity.
  5. Test the ORN wire between the A/C refrigerant pressure switch and the A/C compressor control module for continuity.

Is continuity present in all of the above tests?

Go to Step 18

Go to Step 17

17

Repair the open in the ORN wire, the BLK wire or replace the A/C refrigerant pressure switch. Refer to Wiring Repairs in Wiring Systems and Pressure Cycling Switch Replacement .

Is the repair complete?

Go to Step 37

--

18
  1. Turn the ignition switch to ON.
  2. Turn the A/C switch to OFF.
  3. Test for battery voltage at the A/C switch connector at cavity 3.

Is battery voltage present?

Go to Step 20

Go to Step 19

19

Repair the open in the GRN/WHT wire between the A/C switch and the compressor control module (including S263). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

20
  1. Turn the ignition switch to ON.
  2. Turn the A/C switch to ON.
  3. Test for battery voltage at the A/C switch connector at cavity 2.

Is battery voltage present?

Go to Step 22

Go to Step 21

21

Replace the A/C switch. Refer to Control Assembly Replacement .

Is the repair complete?

Go to Step 37

--

22

Test for battery voltage at the blower speed switch connector cavity 6.

Is battery voltage present?

Go to Step 24

Go to Step 23

23

Repair the open in the PNK/WHT wire between the A/C switch and the blower speed switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

24
  1. Move the blower speed switch to any position except OFF.
  2. Test for battery voltage at the blower speed selector switch connector cavity 1.

Is battery voltage present?

Go to Step 26

Go to Step 25

25

Replace the blower speed switch. Refer to Blower Switch Replacement .

Is the repair complete?

Go to Step 37

--

26

Test for an open in the BLK ground wire between the blower speed switch and G200.

Is an open present?

Go to Step 36

Go to Step 27

27
  1. Disconnect the evaporator temperature sensor connector.
  2. Measure the resistance of the evaporator temperature sensor with a digital multimeter from cavity 1 to cavity 2.

    3. Evaporator Temperature Sensor Resistance
    1.8-2.2 kohms@25°C (77°F)

    Evaporator Temperature Sensor Resistance
    6.3-7.0 kohms@0°C (32°F)

Is the resistance within the specified range?

Go to Step 29

Go to Step 28

28

Replace the evaporator temperature sensor. Refer to Air Conditioning (A/C) Temperature Sensor Replacement .

Is the repair complete?

Go to Step 37

--

29
  1. Start the engine.
  2. Turn the A/C switch to the ON position.
  3. Measure the voltage with a digital multimeter at the A/C compressor control module connector cavity 4.

Is the voltage 0-1 volt?

Go to Step 30

Go to Step 35

30
  1. Start the engine.
  2. Turn the A/C switch to the ON position.
  3. Measure the voltage with a digital multimeter at the powertrain control module (PCM) connector 1 cavity 17.

Is the voltage 0-1 volt?

Go to Step 32

Go to Step 31

31

Repair the open in the YEL/BLK wire between the A/C compressor control module and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

32
  1. Turn the ignition switch to the ON position.
  2. Turn the A/C switch to the OFF position.
  3. Measure the voltage with a digital multimeter at the PCM connector 1 cavity 8.

Is the voltage 0-1.5 volts?

Go to Step 33

Go to Air Conditioning (A/C) Idle Circuit Diagnosis in Engine Controls

33
  1. Turn the ignition switch to the ON position.
  2. Turn the A/C switch to the OFF position.
  3. Measure the voltage with a digital multimeter at the A/C compressor control module connector cavity 8.

Is the voltage 0-1.5 volts?

Go to Step 35

Go to Step 34

34

Repair the short to ground in the GRN/YEL wire or the GRN/WHT wire between the A/C compressor control module and the PCM. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

35

Replace the A/C compressor control module. Refer to Air Conditioning (A/C) Compressor Control Module Replacement .

Is the repair complete?

Go to Step 37

--

36

Repair the open or the short to ground in the wire. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 37

--

37

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Compressor Control Module Voltage Table

Terminal/Wire

Circuit

Normal Value

Condition

1-PNK

Compressor relay

0-1 Volt

Blower switch ON and A/C or Defrost switch ON with engine running (Terminal A 8 at more than 5 volts)

10-14 Volts

Other than above with ignition switch ON

2-3

Not Used

4-YEL/BLK

PCM (A/C idle-up signal)

10-14 Volts

Ignition switch ON, A/C switch or blower switch OFF

0-1 Volt

Ignition switch ON, A/C switch ON and blower switch ON

5-7

Not Used

8-GRN/YEL

PCM (A/C cutout signal)

0-1.5 Volts

A/C not operating

10-14 Volts

A/C operating

9

Not Used

10-GRN/BLK

A/C switch or Defrost switch

0-1 Volt

Blower switch ON and A/C or Defrost switch ON with ignition switch ON

A/C switch or Defrost switch

10-14 Volts

Blower switch OFF and A/C or Defrost switch OFF with ignition switch ON

11-12

Not Used

13-ORN

Refrigerant pressure switch

0-1 Volt

Ignition switch ON

14

Not Used

15-BLK/YEL

Ground

0-1 Volt

Ignition switch ON

16-BLK/WHT

Power source

10-14 Volts

Ignition switch ON

1-BLK/GRY

Evaporator temperature sensor

0-1 Volt

Ignition switch ON

2-BLK/GRY

Evaporator temperature sensor

0.9-1.1 Volts/1.8-2.2 kohms

Evaporator temperature 25°C (77°F) with ignition switch ON

2.2-2.4 Volts/6.3-7.0 kohms

Evaporator temperature 0°C (32°F) with ignition switch ON