Opel Frontera UE. Manual - part 916

6E2–50

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

A/C Clutch Control Circuit Diagnosis

  (Cont'd)

Step

No

Yes

Value(s)

Action

4

IMPORTANT: Before continuing with the diagnosis, the
following conditions must be met:

D

The intake air temperature must be greater than
15

°

C. (60

°

F).

D

The engine coolant temperature must be less
than 119

°

C (246

°

F).

1. A/C “OFF.”
2. Start the engine and idle for 1 minute.
3. Observe the A/C compressor.

Is the A/C compressor clutch engaged even though
A/C has not been requested?

—

Go to 

Step 45

Go to 

Step 5

5

1. Idle the engine.
2. A/C “ON”.
3. Blower “ON”.
4. Observe the A/C compressor.

Is the A/C compressor magnetic clutch engaged?

—

Refer to

Diagnostic

Aids

Go to 

Step 6

6

1. Engine idling.
2. A/C “ON”.
3. Blower “ON”.
4. Observe the “A/C Request” display on the Tech 2.

(Refer to the miscelluneous test)

Does the “A/C Request” display indicate “Yes?”

—

Go to 

Step 34

Go to 

Step 7

7

Temporarily substitute the A/C compressor relay in
place of the A/C thermostat relay, then repeat Step 5.

Did the “A/C Request” display indicate “Yes?”

—

Go to 

Step 8

Go to 

Step 9

8

Replace the original A/C thermostat relay.

Is the action complete?

—

Verify repair

—

9

Dose the blower operate?

—

Go to 

Step 10

Go to 

Step 11

10

Repair the blower.

Is the action complete?

—

Verify repair

—

11

Check for a faulty 10A A/C fuse in the passenger
compartment fuse panel.

Was the 10A fuse OK?

—

Go to 

Step 13

Go to 

Step 12

12

Check for short circuit and make repairs if necessary.
Replace the 10A A/C fuse.

Is the action complete?

—

Verify repair

—

13

1. Ignition “ON.”
2. Use a DVM to check voltage at the positive A/C

switch wire (BRN).

Was voltage equal to the specified value?

B+

Go to 

Step 15

Go to 

Step 14

14

Repair the open wire (BRN) between the A/C switch
and the A/C fuse.

Is the action complete?

—

Verify repair

—

6E2–51

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

A/C Clutch Control Circuit Diagnosis

  (Cont'd)

Step

No

Yes

Value(s)

Action

15

1. Remove the glove box to gain access to the A/C

thermostat.

2. Disconnect the thermostat connector.
3. Attach a fused jumper between ground and the

GRN/RED wire at the thermostat.

4. A/C “ON.”
5. Blower “ON.”

Dose A/C request indicate “YES” on the Tech 2?

—

Go to 

Step 16

Go to 

Step 23

16

1. Ignition “ON.”
2. A/C switch “ON”.
3. Use a DVM to check voltage at the electronic A/C

thermostat.

Was voltage equal to the specified value?

B+

Go to 

Step 20

Go to 

Step 17

17

Check for an open (LT GRN/BLK) wire between the
thermostat and the A/C switch.

Was the wire open?

—

Go to 

Step 18

Go to 

Step 19

18

Repair the open wire (LT GRN/BLK) between the
thermostat and the A/C switch.

Is the action complete?

—

Verify repair

—

19

Replace the A/C switch.

Is the action complete?

—

Verify repair

—

20

Use an ohmmeter to check continuity between the
electronic A/C thermostat and the blower switch.

Was there an open circuit?

—

Go to 

Step 21

Go to 

Step 22

21

Repair the open wire (WHT) between the thermostat
and the blower switch.

Is the action complete?

—

Verify repair

—

22

Replace the electronic A/C thermostat.

Is the an action complete?

—

Verify repair

—

23

Check for an open circuit between A/C thermostat relay
and PCM A/C request terminal (E-15).

Was there an open circuit?

—

Go to 

Step 24

Go to 

Step 25

24

Repair the open circuit between the PCM and A/C
thermostat relay.

Is the action complete?

—

Verify repair

—

25

Check for an open circuit between the engine device
fuse and the A/C thermostat relay (WHT/GRN).

Was there an open circuit?

—

Go to 

Step 26

Go to 

Step 27

26

Repair the open circuit between the engine device fuse
and the A/C thermostat relay.

Is the action complete?

—

Verify repair

—

27

1. Ignition “ON.”
2. Use a DVM to check voltage at the A/C pressure

switch (BRN).

Was voltage equal to the specified value?

B+

Go to 

Step 29

Go to 

Step 28

6E2–52

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

A/C Clutch Control Circuit Diagnosis

  (Cont'd)

Step

No

Yes

Value(s)

Action

28

Repair the open circuit between the 10A A/C fuse and
the pressure switch.

Is the action complete?

—

Verify repair

—

29

Use an ohmmeter to check continuity between the
pressure switch (GRN/WHT) and the A/C thermostat
relay (GRN/WHT).

Was the circuit open?

—

Go to 

Step 30

Go to 

Step 31

30

Repair the open circuit between the pressure switch
and the A/C thermostat relay.

Is the action complete?

—

Verify repair

—

31

Check for damaged pin or terminal at E-15 of the PCM.

Was a damaged pin or terminal found?

—

Go to 

Step 32

Go to 

Step 33

32

Repair the damaged pin or terminal.

Is the action complete?

—

Verify repair

—

33

Replace the PCM.

Is the action complete?

—

Verify repair

—

34

1. Remove the A/C compressor relay.
2. Ignition “ON.”
3. Use a DVM to check voltage at both of the BRN

wires at the A/C compressor relay socket. 

Is the voltage equal to the specified value?

B+

Go to 

Step 36

Go to 

Step 35

35

Repair the faulty BRN wire between the A/C fuse and
the A/C compressor relay .

Is the action complete?

—

Verify repair

—

36

1. A/C compressor relay removed.
2. Engine idling.
3. A/C “ON.”
4. Blower “ON.”
5. Use a DVM to measure voltage between the

GRY/RED wire at the A/C compressor relay socket
and battery+.

Did the DVM indicate the specified value?

B+

Go to 

Step 40

Go to 

Step 37

37

Check for an open GRY/RED wire between PCM
terminal B-14 and the A/C compressor relay.

Was the wire open?

—

Go to 

Step 38

Go to 

Step 39

38

Repair the open GRY/RED wire between the PCM and
the A/C compressor relay.

Is the action complete?

—

Verify repair

—

39

Check for a damaged pin or terminal at B-14 of the
PCM.

Was a damaged pin or a terminal found?

—

Go to 

Step 32

Go to 

Step 33

6E2–53

6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

A/C Clutch Control Circuit Diagnosis

  (Cont'd)

Step

No

Yes

Value(s)

Action

40

1. A/C compressor relay removed.
2. Connect a fused jumper at the A/C compressor

relay socket between either BRN wire and the
BRN/YEL wire.

3. Engine idling.
4. A/C “ON.”
5. Blower “ON.”

Did the compressor magnetic clutch engage?

—

Go to 

Step 41

Go to 

Step 42

41

Repair the A/C compressor relay.

Is the action complete?

—

Verify repair

—

42

Check for an open circuit between the A/C compressor
relay and the A/C clutch.

Was an open circuit found?

—

Go to 

Step 43

Go to 

Step 44

43

Repair the open circuit between the compressor Clutch
and the A/C compressor relay.

Is the action complete?

—

Verify repair

—

44

Service the compressor clutch or replace the
compressor due to a faulty internal overheat switch.

Is the action complete?

—

Verify repair

—

45

1. Remove the A/C compressor relay.
2. Idle the engine.

Is the compressor clutch still engaged when A/C is not
selected?

—

Go to 

Step 46

Go to 

Step 47

46

Repair the short to voltage between the A/C clutch and
A/C compressor relay.

Is the action complete?

—

Verify repair

—

47

1. Reinstall the A/C compressor relay.
2. Remove the A/C thermostat relay.
3. Engine idling.

Is the compressor clutch still engaged when A/C is not
selected?

—

Go to 

Step 48

Go to 

Step 50

48

Use a DVM to check for a short to ground between the
A/C compressor relay and B-14 of the PCM.

Was a short detected?

—

Go to 

Step 49

Go to 

Step 33

49

Repair the short to ground between the PCM and A/C
compressor relay.

Is the action complete?

—

Verify repair

—

50

Repair the short to ground between the A/C thermostat
relay and the electronic thermostat.

Is the action complete?

—

Verify repair

—