Pontiac Fiero 1988 Service Manual page 708

DRIVEABILITY AND EMISSIONS - FUEL INJECTION (PORT) 6E3-C10-3
©
© IGN " O N " , ENGINE " O F F " .
• TURN A/C ON AND OFF AND NOTE A/C CLUTCH.
• CLUTCH SHOULD NOT CYCLE ON AND OFF.
• DOES ST?
NO
©
• WITH ENGINE IDLING AT NORMAL
OPERATING TEMP. TURN A/C ON AND OFF.
• CLUTCH SHOULD CYCLE ON AND OFF.
• DOES IT?
NO
©[
PLACE A/C CONTROL IN A/C
MODE.
"SCAN** T O O L SHOULD
DISPLAY A / C REQUEST " O N "
DOES IT?
YES
H Z
® IGN " O N " , A/C " O N " .
• ENGINE " O F F " .
DISCONNECT A/C RELAY.
PROBE HARNESS TERM.
A & D CKT 50 & 67 WITH
TEST LIGHT TO GND.
LIGHT " O N " BOTH
• JUMPER CKT 50 TO
CKT 59.
• DOES A/C CLUTCH
ENGAGE?
NO LIGHT,
OWE OR BOTH
REPAIR OPEN
IN CKT THAT
DID NOT
LIGHT.
YES NO
©
ENGINE IDLING, A/C " O N " .
PROBE CKT 459 WITH A
TEST LIGHT TO 12 VOLTS.
LIGHT " O N "
I
LIGHT " O F F "
CHART C - 1 0
A/C CLUTCH CONTROL DIAGNOSIS
2.8L "P" SERIES (PORT)
Y E S
ZZH
DISCONNECT A/C RELAY.
PROBE CKT 459 WITH A
TEST LIGHT TO 12 VOLTS.
YES
H Z
LIGHT " O N "
A/C CIRCUIT O K ,
REFER TO
DIAGNOSTIC AIDS
ON FACNG PAGE.
NO
CKT 459
SHORTED TO
GROUND OR
FAULTY ECM.
SEE ECM Q U A D
DRIVER CHECK
(CHART C-1).
LIGHT "OFF
Z I Z Z
FAULTY
RELAY.
• DISCONNECT PRESS. CYCLING SWITCH.
• PROBE CKT 66 WITH A TEST LIGHT TO
GROUND.
LIGHT " O N "
LIGHT " O F F "
JUMPER HARNESS
TERMINALS TOGETHER.
" S C A N " S H O U L D
DISPLAY A/C REQUEST
" O N " .
DOES IT?
©
OPEN OR SHORT TO GND IN
CKT 66. IF A/C FUSE IS B L O W N ,
CHECK CKTS 6 6 , 6 7 , 50 AND 59
FOR SHORT TO GND.
YES
ZEZ
A/C S Y S T E M L O W ON
CHARGE, FAULTY CONN.,
OR FAULTY PRESSURE
CYCLING SWITCH.
CHECK
- OPEN CKT 59 TO
CLUTCH.
- OPEN CLUTCH COIL
- FAULTY HIGH
PRESSURE CUT-OUT
SWITCH
NO
Z E
OPEN CKT 67,
FAULTY
C O N N E C T I O N ^ ) ,
OR FAULTY E C M .
SEE ECM Q U A D
DRIVER CHECK
(CHART C-1).
FAULTY
RELAY.
OPEN OR SHORT
TO VOLTAGE IN
CKT 459,
FAULTY
CONNECTION,
OR ECM. SEE
ECM QUAD
DRIVER CHECK
(CHART C-1).
7-1-87
k
7S 3434-6E