Pontiac Fiero 1988 Service Manual page 1058

AIR CONDITIONING: COMPRESSOR CONTROLS
C60, MANUAL
S Y S T E M CHECK TABLE
ACTION NORMAL RESULT
1. Turn Ignition Switch to RUN and start engine
Move A/C Mode Selector to OFF then to MAX
A click can be heard when the clutch engages
2. Move A/C Mode Selector between OFF and
MAX several times
Verify that clutch engages in MAX position
Clutch plate movement can be seen on the front of
the compressor pulley
If clutch does not engage, go to step 4
If clutch operates normally, continue to step 3
3. Put A/C Mode Selector in MAX to engage
clutch
Engine Coolant Fan runs when Compressor is
engaged
Air moves freely through condenser
Feel the suction (cold) and output (warm) pipes of
the Compressor
If there is not a wide temperature difference after
the Compressor has run for several seconds, see
Section IB for Refrigerant and Compressor
diagnostics
4. Turn off Ignition Switch and check refrigerant
pressure at the low side service fitting
If pressure is less than 207 kPa (30 psi), refer to
Section IB for refrigerant diagnostics
If refrigerant pressure is higher than 207 kPa (30
psi), isolate trouble conditions using procedures in
System Diagnosis
S Y S T E M DIAGNOSIS
L4V1NR
® Use
the Isolation Tests below to
choose the
proper diagnostic test.
ISOLATION T E S T (TABLE 1)
Refer to System Diagnosis when & result is not normal
Measure: VOLTAGE
At: A / C COMPRESSOR CONTROL RELAY
CONNECTOR
(Disconnected)
Conditions:
• Ignition Switch: RUN (Engine need not
be running)
• A/C Mode: NORM
• Temperature Outside Car: ABOVE 60°F
( I P C )
Measure
Between
D (BLK/WHT)
& Ground
A (LT BLU) &
Ground
Correct
Voltage
Battery
Battery
For Diagnosis
Seel
See
2
• If both voltages are correct, leave A/C
Compressor Control Relay disconnected
and go to Table 2.
1. Check BLK/WHT (922) wire for an open.
2. Do Tfest C.
(Continued on next page)