HVAC Compressor Clutch Does Not Engage. Chevrolet Metro 2000

For 1990-2009 cars

Table 1: | Compressor Control Module Voltage Table

Step | Action | Yes | No
--- | --- | --- | ---
1 | Was the HVAC System Check performed? | Go to Step 2 | Go to HVAC System Check

2

Important: Before performing this diagnostic, verify that the air conditioning (A/C) refrigerant system is in the correct mechanical condition in order to avoid a misdiagnosis.Inspect the refrigerant level.Inspect the system for leaks.

1. Disconnect the A/C compressor clutch connector.

Start the engine.

2. Press the A/C switch to the ON position.
3. Move the blower speed selector switch to any position except the OFF position.
4. Connect a test lamp between the terminal of the A/C compressor clutch connector and ground.

Does the test lamp light?

Go to Step 3

Go to Step 4

3 | Replace the A/C compressor clutch. Refer to Compressor Clutch Coil Replacement . Is the repair complete? | Go to HVAC System Check | --

4

1. Remove the relay box from the wheelhousing.
2. Backprobe the connector of the A/C compressor clutch relay with a test lamp from terminal 3 to ground.

Does the test lamp light?

Go to Step 5

Go to Step 6

5 | Repair the open in the BLK/RED wire between the A/C compressor clutch relay and the A/C compressor clutch. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | Go to HVAC System Check | --
6 | Backprobe the connector of the A/C compressor clutch relay with a test lamp from terminal 4 to ground. Does the test lamp light? | Go to Step 8 | Go to Step 7
7 | Repair the open in the RED/WHT wire between the A/C fuse and the A/C compressor clutch relay. Is the repair complete? | Go to HVAC System Check | --
8 | Backprobe the connector of the A/C compressor clutch relay with a test lamp from terminal 1 to ground. Does the test lamp light? | Go to Step 10 | Go to Step 9
9 | Repair the open in the LT GRN wire between the junction block and the A/C compressor clutch relay. Is the repair complete? | Go to HVAC System Check | --

10

1. Disconnect the connector of the A/C compressor control module.
2. Connect a fused jumper wire to the connector of the A/C compressor control module from terminal 7 to ground.

Does the A/C compressor clutch engage?

Go to Step 11

Go to Step 12

11 | Connect a test lamp to the connector of the A/C compressor control module from terminal 8 to ground. Does the test lamp light? | Go to Step 16 | Go to Step 15
12 | Backprobe the connector of the A/C compressor clutch relay with a fused jumper wire from terminal 2 to ground. Does the compressor clutch engage? | Go to Step 14 | Go to Step 13
13 | Replace the A/C compressor clutch relay. Refer to Compressor Relay Replacement . Is the repair complete? | Go to HVAC System Check | --
14 | Repair the open in the PNK wire between the A/C compressor clutch relay and the A/C compressor control module. Is the repair complete? | Go to HVAC System Check | --
15 | Repair the open in the BLK/WHT wire between S202 and the A/C compressor control module. Is the repair complete? | Go to HVAC System Check | --
16 | Connect a test lamp to the connector of the A/C compressor control module from terminal 3 to B+. Does the test lamp light? | Go to Step 18 | Go to Step 17
17 | Repair the open in the BLK/BLU wire or in the BLK wire between terminal 3 of the A/C compressor control module and G201. Is the repair complete? | Go to HVAC System Check | --
18 | Connect a test lamp to the connector of the A/C compressor control module from terminal 9 to B+. Does the test lamp light? | Go to Step 20 | Go to Step 19
19 | Repair the open in the BLK wire between terminal 9 of the A/C compressor control module and G201. Is the repair complete? | Go to HVAC System Check | --
20 | Connect a test lamp to the connector of the A/C compressor control module from terminal 11 to ground. Does the test lamp light? | Go to Step 22 | Go to Step 21
21 | Backprobe the connector of the A/C switch with a test lamp from terminal 2 to ground. Does the test lamp light? | Go to Step 24 | Go to Step 23
22 | Connect a test lamp to the connector of the A/C compressor control module from terminal 12 to B+. Does the test lamp light? | Go to Step 27 | Go to Step 28
23 | Backprobe the connector of the A/C switch with a test lamp from terminal 1 to ground. Does the test lamp light? | Go to Step 25 | Go to Step 26
24 | Repair the open in the BLU/WHT wire between the A/C switch and the A/C compressor control module. Is the repair complete? | Go to HVAC System Check | --
25 | Replace the A/C switch. Refer to Air Conditioning (A/C) Cooling Fan Switch Replacement . Is the repair complete? | Go to HVAC System Check | --
26 | Repair the open in the PNK/BLK wire between S233 and the A/C switch. Is the repair complete? | Go to HVAC System Check | --

27

1. Disconnect the evaporator temperature sensor connector.
2. Connect a J 39200 to the connector of the evaporator temperature sensor from terminal 1 to terminal 2.
3. Measure the resistance at room temperature.

Is the resistance greater than 2000 ohms?

Go to Step 32

Go to Step 33

28

1. Disconnect the refrigerant pressure switch.
2. Connect a test lamp to the connector of the refrigerant pressure switch between terminal 1 and B+.

Does the test lamp light?

Go to Step 29

Go to Step 31

29 | Inspect for an open in the ORN/BLK wire between the A/C compressor control module and the refrigerant pressure switch. Did you find an open? | Go to Step 39 | Go to Step 30
30 | Replace the refrigerant pressure switch. Refer to Pressure Cycling Switch Replacement . Is the repair complete? | Go to HVAC System Check | --
31 | Repair the open in the BLK wire between the refrigerant pressure switch and G103. Is the repair complete? | Go to HVAC System Check | --
32 | Replace the evaporator temperature sensor. Refer to Air Conditioning (A/C) Temperature Sensor Replacement . Is the repair complete? | Go to HVAC System Check | --

33

1. Reconnect the evaporator temperature sensor.
2. Connect a J 39200 from connector terminal 4 of the A/C compressor control module to connector terminal 10 of the A/C compressor control module.
3. Measure the resistance.

Is the resistance greater than 2000 ohms?

Go to Step 34

Go to Step 35

34 | Repair the open in the WHT/BLU wire or in the YEL/GRN wire between the A/C compressor control module and the evaporator temperature sensor. Is the repair complete? | Go to HVAC System Check | --

35

1. Disconnect the powertrain control module (PCM) connector C3.
2. Connect a J 39200 to the connector of the A/C compressor control module from terminal 5 to ground.
3. Measure the resistance.

Is the resistance infinite?

Go to Step 37

Go to Step 36

36 | Repair the short to ground in the LT GRN/RED wire between the PCM and the A/C compressor control module. Is the repair complete? | Go to HVAC System Check | --

37

1. Reconnect the PCM connector C3.
2. Back out the LT GRN/RED wire from terminal 5 of the connector of the A/C compressor control module.
3. Connect the connector of the A/C compressor control module.
4. Disconnect the A/C compressor clutch connector.
5. Connect a test lamp between the connector terminal of the A/C compressor clutch and ground.

Does the test lamp light?

Go to Air Conditioning (A/C) Idle Circuit Diagnosis 1.0L or Air Conditioning (A/C) Idle Circuit Diagnosis 1.3L in Engine Controls

Go to Step 38

38 | Replace the A/C compressor control module. Refer to Air Conditioning (A/C) Compressor Control Module Replacement . Is the repair complete? | Go to HVAC System Check | --
39 | Repair the open in the ORN/BLK wire between the A/C compressor control module and the refrigerant pressure switch. Is the repair complete? | Go to HVAC System Check | --

#### Compressor Control Module Voltage Table

Terminal/Wire | Circuit | Normal Value | Condition
--- | --- | --- | ---
1/BLU/RED | A/C idle-up control | 0-1 Volt | The ignition switch, the blower switch, and the A/C switch are ON.
10-14 Volts | The ignition switch is ON.
2 | Not Used
3/BLK/BLU | Ground | 0-1 Volt | The ignition switch is ON.
4/WHT/BLU | Evaporator temperature input | 1.2-1.5 Volts (2107-2575 ohms | The evaporator temperature is approximately 15°C (59°F) with the ignition switch ON.
2.1-2.4 Volts (4609-5095 ohms) | The evaporator temperature is approximately 0°C (32°F) with the ignition switch ON.
5/LT GRN/RED | A/C cutout signal | 10-14 Volts | The blower switch and the A/C switch are ON with the engine running.
0-1 Volt | The ignition switch is ON.
6 | Not Used
7/PNK | Compressor clutch relay control | 0-1 Volt | The blower switch and the A/C switch are ON with the engine running.
10-14 Volts | The ignition switch is ON.
8/BLK/WHT | Ignition power | 10-14 Volts | The ignition switch is ON.
9/BLK | Ground | 0-1 Volt | The ignition switch is ON.
10/YEL/GRN | Evaporator temperature sensor ground | 0-1 Volt | The ignition switch is ON.
11/BLU/WHT | A/C request signal | 10-14 Volts | The ignition switch, the blower switch, and the A/C switch are ON.
0-1 Volt | The ignition switch is ON, and the blower switch or the A/C switch is OFF.
12/ORN/BLK | Refrigerant pressure switch signal | 0-1 Volt | The refrigerant pressure is 200-3200 kPa (28.4-454.4 psi) with the ignition switch ON.
10-14 Volts | The ignition switch is ON.