Pontiac Fiero 1988 Service Manual page 1061

AIR CONDITIONING: COMPRESSOR CONTROLS
C 6 0 , M A N U A L
(Continued from previous page)
A : E C M C O M P R E S S O R C O N T R O L
T E S T ( T A B L E D
Measure: VOLTAGE
At: ECM CONNECTORS CI & C2
(Disconnected)
Conditions:
• Ignition
Switch: RUN (Engine not
running)
o A / C Mode: NORM
• Temperature Outside Car: ABOVE 60°F
(16°C)
• A / C Compressor Control Relay:
CONNECTED
Measure Correct
For Diagnosis
Between Voltage
For Diagnosis
C2/B8 (LT
BLU)&
Ground
Battery Seel
C1/C2 (DK
BLU)&
Ground
Battery See 2
• If both voltages are correct, go to Table 2.
1. Check for open in LT BLU (67) wire.
2. Check for an open in the DK BLU (459)
wire. If wire is good, replace A/C Com-
pressor Control Relay.
A : E C M C O M P R E S S O R C O N T R O L
T E S T ( T A B L E 2)
Connect: FUSED JUMPER
At: ECM CONNECTOR C I (Connected)
Conditions:
• Ignition Switch: RUN
• A / C Mode: NORM
• Temperature Outside Car: ABOVE 60°F
(16°C)
Jumper
Between
Correct Result For Diagnosis
C1/C2 (DK
BLU)&
Ground
A/C
Compressor
Control Relay
operates and
A/C
Compressor
Clutch
engages
Seel
• If the result is correct, but A/C System
does not operate normally, condition is due
to the ECM. Refer to Section 6E for ECM
diagnostic procedures.
1. Replace the A/C Compressor Control
Relay.
B: A/C COMPRESSOR CLUTCH TEST
Measure: VOLTAGE
At: A / C COMPRESSOR CLUTCH
CONNECTOR (Disconnected)
Conditions:
• Ignition Switch: RUN (Engine not
running)
• A / C Mode: NORM
• A / C Compressor Control Relay:
DISCONNECTED
• A / C Compressor Control Relay
Terminals D and B: JUMPERED
Measure
Between
DK GRN &
Ground
DK GRN
& BLK
Correct
Voltage
Battery
Battery
For Diagnosis
Seel
See
2
• If both voltages are correct, but clutch does
not engage when connected, replace the
A/C Compressor Clutch.
1. Check for open in DK GRN (59) wire.
2. Check for open in BLK (150) wire to
ground. Check that A/C High Pressure
Cut-Out Switch is closed. If it is open,
replace it.