GMC Chevrolet Camaro 1998 Service Manual page 136

1-26 HVAC System - Manual HVAC
Compressor Clutch Engagement
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's are set.
Were you sent here from the VDOT Refrigerant Charge Go to the VDOT
1
Diagnostic Table?
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System
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Go to Step 2 Performance table
1.
Let the engine run at idle speed.
2.
Set the A/C control to the NORM A/C mode.
2
3.
Set the blower motor speed to high.
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4.
Set the temperature control to full cold.
Does the clutch engage? Go to Step 3
Go to Step 12
Check for a knocking noise coming from the compressor.
3
Cycle the compressor ON and OFF to verify the source of
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Go to the VDOT
the noise.
System
Is there noise coming from the compressor? Go to Step 4 Performance table
4
Inspect the A/C drive belt for slippage.
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Is the noise due to belt slippage?
Go to Step 5 Go to Step 6
Replace the A/C drive belt. Refer to Drive Belt
5
Replacement (AIC) in Engine Mechanical. -
Is the repair complete? System OK Go to Step 9
6
Listen to the compressor for the noise.
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Is the noise coming from the compressor? Go to Step
7
Go to Step 9
7
Check the A/C lines for contact with other components.
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Is there contact with other components? Go to Step B Go to Step 9
Reposition or replace the A/C lines as necessary.
Go to the VDOT
8
Is the repair complete?
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System
System OK Performance table
Recover and recharge the A/C system. Refer to
9
Refrigerant Recovery and Recharging
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(
Is .the repair complete?
System OK
Go to Step 10
Refer to the noise diagnosis table. Go to the VDOT
10
Is the noise coming from the compressor?
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System
Go to Step 11 Performance table
Replace the A/C compressor. Refer to Compressor
Go to the VDOT
11
Replacement (3.BL) or Compressor Replacement (5.7L).
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System
Is the noise still present? Performance table System OK
1.
Turn the ignition to the OFF position.
2.
Disconnect the clutch wires at the compressor.
3.
Connect a jumper wire from ground to one of the
12
compressor clutch terminals.
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4.
Connect a fused-jumper wire from the positive battery
post to the other compressor clutch terminal.
Does the clutch engage? Go to Step 13 Go to Step 14
1.
Repair the electrical circuit to the compressor clutch.
2.
Run the engine at idle speed.
13
3.
Set the A/C control to the A/C mode.
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4.
Set the blower motor speed to high.
Go to the VDOT
5. Set the temperature control to fuU cold.
System
Does the clutch engage? System OK Performance table
Replace the clutch coil. Go to the VDOT
14
Is the repair complete?
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System
System OK Performance table
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