Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL KL]
23
A/C DOES NOT WORK
DESCRIPTION A/C compressor magnetic clutch does not engage when A/C is turned on
POSSIBLE
CAUSE
• Improper refrigerant charging amount
• Open A/C magnet clutch
• Poor ground of A/C magnet clutch
• A/C relay stuck to open
• Power steering stuck to short
• Open circuit between A/C switch and PCM through both A/C pressure switches
• Short to ground circuit between power steering pressure switch and PCM
• A/C low pressure switch stuck to open
• Open circuit between A/C relay and A/C magnet clutch
• A/C high pressure switch stuck open
• A/C compressor seized
STEP INSPECTION
ACTION
1
Retrieve and record any continuous memory,
KOEO and KOER.
Are there any DTCs displayed?
Yes Go to appropriate DTC test.
No
Go to next step.
2 Disconnect power steering pressure switch
connector.
Is there continuity between connector terminal
and ground?
Yes Short to ground.
Repair or replace wire harness.
No Check for short to ground at power steering pressure
switch.
If switch is okay, go to next step.
If short exists, replace switch.
3
Disconnect A/C compressor connector.
Start engine and turn A/C switch on.
Is there correct voltage at terminal of A/C
compressor magnet clutch connector?
Specification
More than 10.5 V
Yes Check for ground condition of A/C compressor magnet
clutch.
If ground condition is okay, check for open circuit of
magnet clutch.
No Go to next step.
4 Disconnect A/C low pressure switch and A/C
high pressure switch connectors.
Connect jum per between terminals of harness
connectors.
Connect NGS tester to DLC.
Access ACCS PID on NGS tester.
Turn ignition switch ON.
Turn A/C switch on and set blower fan at any
speed.
Does ACCS PID read ON?
Yes Check A/C high pressure switch and low pressure switch
operation.
Replace malfunctioning switch.
If both switches okay, Go to next step.
No
Check following(s):
• A/C switch stuck to open.
• Open circuit among both A/C pressure switches and
PCM.
• Open circuit of blower motor fan switch and resister (if
blower motor does not operate).
5 Remove jum per wires from switch connectors.
Reconnect connectors to both switches.
Start engine and turn A/C switch on.
Verify fans operation.
Do both fans operate?
Yes Check for stuck to open A/C relay.
Replace as necessary.
No
Check follows and repair or replace as necessary:
• Refrigerant charging amount.
• Seized A/C compressor.
6
Verify test results. If okay, return to diagnostic index to service any additional symptoms.
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