1988 PONTIAC FIERO ignition

AIR CONDITIONING: COMPRESSOR CONTROLS
(Continued from previous page) B: AIC COMPRESSOR CLUTCH TEST
A: ECM COMPRESSOR CONTROL TEST
(TABLE
3)
Connect: FUSED JUMPER
At: ECM CONNECTOR (Disconnected)
Conditions: lgnition Switch: RUN (Engine not
running)
@ AIC Mode: NORM
Temperature Outside Car: Above
60 OF
(16°C)
Jumper Correct
Between Action Diagnosis
engages
A2
on Conn
61
(LT BLU)
& Ground
If action is correct but A/C system does not
operate under normal conditions, condition
is due to ECM. Refer to Section 6E for ECM
diagnostics. Compressor
Control Relay
operates and
AfC Clutch
Between 1 Voltage I Diagnosis
Measure:
VOLTAGE
At: COMPRESSOR CLUTCH CONNECTOR
(Disconnected) Ignition Switch: RUN (Engine
not
running)
r AIC Mode: NORM
@ AIC Compressor Control Relay
disconnected
AIC Compressor Control Relay
terminals A and E jumpered
r Temperature Outside Car: Above 60°F
(1 6°C)
See 1
B (DK GRN) & /
Ground I See 1
Measure I Correct
(DK GRN) '1 Battery I See 2 A (BLK)
For
- -
e If voltages are correct but clutch does not
engage, replace the Compressor Clutch.
1. Check for open in DK GRN (959) wire.
2. Check for open in BLK (150) wire.
6: AIC COMPRESSOR FUNCTlON
CONTROL TEST
Measure: VOLTAGE
At: AIC CONTROL HEAD
Conditions: Ignition Switch: RUN (Engine need
not be running)
@ AIC Mode: NORM
Temperature Outside Car: Above
60°F
(16°C)
Measure I Correct
Between Voltage
& Ground
If voltages are correct, go to
61.
1. Check for open CLSTR Fuse or open
For
Diagnosis
See 1
B (LT GRN) &.
Ground -
C1. Remove the connectors from the A/C Pressure
Cycling Switch and the
A/C High Pressure Cut-
Out Switch and connect a fused jumper between
the terminals of the connectors.
If either switch is open, battery voltage will
be present at al E of the AIC Corn-
pressor Control Relay when the jumper is
connected.
Battery
If the Ale Pressure Cycling Switch is open,
refer to Section
1B to check for normal
refrigerant charge. If refrigerant charge is
normal replace the switch. If refrigerant
charge is low, follow procedures in Section
1B for refrigerant diagnostics. Replace
AfC
Control Head
0 If
the NC Nigh Pressure Cut-Out Switch is
open replace
it.

AIR CONDITIONING: COMPRESSOR CONTROLS
667, ELECTRONIC
r If both switches are good but battery volt-
age is not present at the
A/C Compressor
Control Relay, check the wiring between
switches for an open (see schematic).
SYSTEM DlPaGNOSlS
V8 VINF, V8 VIN 8
s Use the Isolation Test below to choose the
proper diagnostic tests.
r Tests follow the Isolation Test.
lSOLATlON TEST (TABLE 2)
Connect: FUSED JUMPER
At:
A/C PRESSURE CYCLING SWITCH
CONNECTOR (Disconnected)
Conditions: Ignition Switch: RUN (Engine need
not be running)
Q NC Mode: NORM
Q Temperature Outside Car: Above 60°F
(1 6°C)
I Jumper I Correct I For
lSOLATlOlU TEST (TABLE 1)
I Measure: VOLTAGE
AIC Mode:
NORM
@ Temperature Outside Car: Above 60°F
(1 6°C)
At:
AIC PRESSURE
CYCLING SWITCH
CONNECTOR (Disconnected)
Conditions:
lgnition Switch: RUN (Engine need
not be running) Between
B (LT GRN) &
A (LT
BLU)
If action is correct, refer to Section 1B for
procedure to check refrigerant pressure. If
refrigerant pressure is
normal, replace the
I (zz) & I Battery I Do Test B I
Measure
Between
A: AIC COMPRESSOR CLUTCH TEST
Action
Clutch
Engages
Diagnosis
Do Test A
Correct
Voltage
.
If voltage is correct, leave Pressure Cycling
Switch disconnected and go to Table
2.
Measure: VOLTAGE
At:
A/C COMPRESSOR CLUTCH
CONNECTOR (Disconnected)
Conditions:
lgnition Switch: RUN (Engine not
running)
0 A/C Mode: NORM
Temperature Outside Car: Above
60°F
(16°C)
For
Diagnosis
(Continued on next page)
Measure
Betvveen
B (DK GRN) &
Ground
B (DK GRN) &
A (BLK)
Q If voltages are correct but clutch does not
engage, replace the Compressor Clutch.
1. Check that A/C Nigh Pressure Cut-Out
Switch is closed (see schematic).
If it is
open, replace it. Check for
an open in the
LT BLU (67) and DK GRN (59) wires.
2. Check for an open in the BLK (150) wire.
Check that ground 6112 is clean and tight.
Correct
\joltage
Battery
Battelr
For
Diagnosis
See 1
See 2

AIR CONDITIONING: COMPRESSOR CONTROLS
B: AIG COMPRESSOR FUNGTlON
CONTROL TEST
Measure: VOLTAGE
At: AIG CONTROL HEAD
Conditions:
e Ignition Switch: RUN
@ A/C Mode: NORM
@ Temperature outside car: above 60°F
(16°C)
1 Measure I Correct 1 For 1
Between I Voltage I Diagnosis I
1 ) 1 Battery 1 See 1 I
r If voltages are correct, check for an open in
the LT
GRN (66) wire.
B (LT GRN) &.
Ground
1. Check for an open CLSTR Fuse or open
BRN
(950) wire.
The compressor for the air conditioning system
is belt driven by the engine through the Com-
pressor Clutch. The clutch allows the compressor
to be disengaged when air conditioning is not re-
Battery
quired or to remove the air conditioning load from
the engine when necessary. Replace
A/C
Control Head
Operation of the compressor depends on the
particular A/C mode selected by the driver. When
the
A/C Mode is in MAX, NORM, BI-LEVEL or
DEF battery voltage is applied through the
CLSTR Fuse and
A/C Control Head Mode Selec-
tor Switch to the remaining circuits.
V6 VIN S
For vehicles equipped with the V6 VIN S
engine the path to the
A/C Compressor Control
Relay is through the
AlC Pressure Cycling
Switch and the
A16 Nigh Pressure Cut-Out
Switch which are both normally closed. The
Ale Pressure Cycling Switch opens when
refrigerant pressure drops to a point where the
evaporator may begin to ice.
It closes again
when the pressure rises to the point where
addi-
tional cooling is required. This action causes the
compressor to cycle on and off. The
Ale High
Pressure Cut-Out Switch opens when
refrigerant pressure is too high for
nomd oopr-
ation.
The AIC Compressor Control Relay is operated
by the EGM. When the ECM receives the
A/C ON
signal at Terminal
B8, it grounds Terminal A2,
energizing the relay. When the relay is energized,
voltage is applied to the
A/C Compressor Clutch
through the contacts of the relay. If the ECM de-
termines that engine load should be reduced,
such as during full throttle, the
A/C Compressor
Control Relay is de-energized which removes volt-
age from the
A/C Compressor Clutch thus remov-
ing the
A/C load from the engine.
V8 VlN F, V8 VllU 8
From the AlC Control Head voltage is
applied to the
A/@ Cornpressor Clutch through
the Pressure Cycling Switch and the
A/@ High
Pressire Cut-Out Switch. The Pressure Cycling
Switch is normally closed but opens when
refrigerant pressure drops below
172 kPa (25
psi). It closes again when refrigerant pressure
rises enough that additional cooling is required.
This action causes the
A/C Compressor to cycle
on and off so that the evaporator temperature does
not drop low enough to cause icing. The
A/
C High Pressure Cut-Out Switch opens if
refrigerant pressure rises to a point which is too
high for normal operation.
When voltage is applied to the compressor
clutch it is also applied to the ECM at
Terminal
B8 on Connector 61. The ECM will then increase
the engine idle speed while the
A/G Compressor
Clutch is engaged.
From the
AlC Control Head voltage is
applied to the
A/C Compressor Clutch though
the Pressure Cycling Switch and the AIC High
Pressure Cut-Out Switch. The Pressure
Cychg
Switch is normally closed but opens when
refrigerant pressure
drops below 172 kPa (25
psi). It closes again when refrigerant pressure
rises enough that
additional cooling is required.
This action causes the
A/C Compressor to cyde
on and off so that the evaporator teqerature
does not drop low enough to cause icing. The
A/C High Pressure Cut-Out Switch opens if
refrigerant pressure becomes too high for nor-
mal operation.

AIR CONDITIONING: AIR DELIVERY I g
667, ELECTRONIC
TROUBLESHOOTING
HINTS
Try the following checks before doing System
Diagnosis.
1. Check for vacuum to the vacuum tank at the
BLACK Hose from the engine vacuum
source and at the VIOLET Rose to the
AIC
Vacuum Solenoid Module.
Check the operation of the Temperature
Valve by setting the Temperature Selector
to COLD and then moving it to ROT.
Observe that the valve moves through its
full range each time the Temperature Selec-
tor is changed from one end of the range to
the other. If the valve is not fully closing or
opening, check that the valve is free to move
and that none of the linkage is binding.
3. Check that Heater Water Bypass Valve
operates in MAX
AIC Mode.
Go to the AIC System Check in 8A-62 for a
guide to normal operation of the Air
Delvery
System.
Go to System Diagnosis
in this section for
diagnostic tests.
SYSTEM DIAGNOSIS
Engine warm and running at idle.
If air flow does not come from the proper
outlets under one or more operating modes,
at least one of the air valves is not moving to
the proper position.
@ Check the operation of the air valves using
the following chart. Put Blower switch in
HI
to give a strong flow of air.
COMPONENT LOCATION Page-Figure
AIC Defrost Vacuum Actuator ..... Behind IIP, on LH side of plenum .............
AIC Temperature Door Motor ...... Behind IIP, on RH side of plenum. ............
AIC Vacuum Solenoid Module ...... Behind IIP, on RH side of plenum. ............
Check Valve. .................... Behind engine, to right of master brake cylinder.
Fuse Block.
..................... Behind LH side of IIP, below light switch. ......
Neater Water Bypass Valve. ....... RH front of engine
Lower Mode Vacuum Actuator
..... Behind IIP, on LH side of plenum .............
Outside Air Vacuum Actuator. ..... Behind IIP, on RH side of plenum. ............
Upper Mode Vacuum Actuator ..... Behind IIP, on LH side of plenum .............
.. Vacuum Tank ................... Lower LH front corner of engine compartment
6200
.......................... Behind IIP, left of steering column ............
S125. .......................... Engine harness, top LH rear of engine .........
........ S201. .......................... IIP harness, behind instrument cluster.
........ S205. .......................... IIP harness, behind instrument cluster.
(Disconnected)
Condition:
IgnEon Swgch: ON
AIR DOOR POSITION TABLE A: AIC CONTROL HEAD VOLTAGE TEST
Measure
Between I Correct Vdtage / For Diagmsk I
Conditions: ignition Switch: RUN (Engine Running)
Blower Switch: HI
I"(BRNIWIFDI & Ground Battery ( See1 I
Measure: VOLTAGE
At:
A/C CONTROL HEAD CONNECTOR 61
I I
@ If voltages are correct, go to tests B and C.
(Continued on facing page)
Mdifional tests of the AIC Vacum System are
(950) wire.
2- ~hd for op in BLK (150) rrire to given in Seclion 1B.

WARNINGS AND ALARMS: CHIMES
TROUBLESHOOTING H lNTS
* Try the following checks before doing the
System Check.
1. Check the STOP HAZ Fuse by observing
the Hazard Lights Operation.
2. Check the GAGES Fuse by observing the
BRAKE Warning Indicator with the Park
Brake applied and the Ignition Switch in
RUN.
3. Check 6200 by operating the Cigar Lighter.
4. If the FASTEN BELT chime reminder and
indicator operate continuously, replace
Audio Alarm Assembly.
5. If the Park Lights are operating normally
and only the Lights-On reminder operates
incorrectly, replace the Audio Alarm Assem-
bly.
Go to System Check for a guide to normal
operation.
Go to System Diagnosis for diagnostic tests.
SYSTEM CHECK
* Use the System Check Table as a guide to
normal operation.
COMPONENT LOCATlON Page-Figure
Convenience Center
.............. Behind IIP, to right of steering column. ........ 201-10-A
Fuse Block.
..................... Behind LH side of IIP, below light switch. ...... 201-10-A
Ignition Key Warning Switch
...... Upper part of steering column
Seatbelt Switch. ................. In driver's seatbelt buckle
C210
(11 cavities) ................ Behind IIP, on RH lower side of steering column. 201-
9-A
6325 (1 cavity) .................. At LH door sill, base of center pillar
6200 .......................... Behind IIP, left of steering column ............ 201-10-A
S204. .......................... IIP harness, behind instrument cluster. ........ 201-10-A
S205. .......................... IIP harness, behind instrument cluster. ........ 201-10-A
S225. .......................... I/P harness, behind instrument cluster. ........ 201-10-A
S227. .......................... IIP harness, behind instrument cluster. ........ 201-10-A
SYSTEM CHECK TABLE
ACTION
Sit in the driver's
seat and close the
driver's door
Turn the Ignition
Switch to RUN
Do not buckle the
seatbelt
NORMAL RESULT
A slow chime alarm
sounds
The FASTEN
BELTS Indicator
lights in the
Instrument Cluster
The chime stops and
the indicator shuts
off after 4 to
8
(Continued from previous column)
buckle
seatbelt
ignition, open the
LH front door
I seconds
(Continued in next column)
(Continued on facing page)

WARNINGS AND ALARMS: CHIMES I
(Continued from facing page) (Continued from previous column) B: KEY IN IGNITION INPUT TEST
e Refer to System Diagnosis when a result is
not normal.
SYSTEM DIAGNOSIS
Do the tests listed lor your symptom in the
Symptom Table below.
e Tests follow the Symptom Table.
SYMPTOM TABLE
SYMPTOM DO TEST I
1 None of the Alarms 1 A: Audio Alarm I
(Continued in next column)
A: AUDIO ALARM ASSEMBLY TEST
At: CONVENIENCE CENTER
e Audio Alarm Module Removed
The FASTEN BELTS
chime reminder oper-
ates when the
Seatbelt
is buckled
The FASTEN BELTS
Indicator does not op-
erate, but the
FAS-
TEN BELTS chime
operates
The FASTEN BELTS
Indicator is always on,
but chime operates
properly
Only the Lights-On
Reminder does not
operate
Connect Correct
Between
I Result Diasnosis
C: Fasten Belts
Input Test
D: FASTEN
BELTS Indicator
Test
D: FASTEN
BELTS Indicator
Test
E: Lights-On In-
put Test
If all results are correct and all the
chime functions were not working, re-
place the Audio Alarm Assembly.
1. Check the ORN (140) wire.
2. Check the BLK/WHT (150) wire for an
oDen to ground.
At: CONVENIENCE CENTER
LT GRN (80) and TAN (159) wires for an
open (see schematic).
2. Check Ignition Key Warning Switch and
LT GRN (80) wire for a short to ground
(see schematic).

WARNINGS AND ALARMS: CHIMES
6: FASTEN BELTS INPUT TEST
At: CONVENIENCE CENTER
Ignition Switch: RUN
If the above results are correct, replace
the Audio Alarm Assembly.
Buckle
LH Front
Seatbelt
1. Check PNKIBLK (39) wire for an open.
2. Check the Seatbelt Switch, and BLK (238)
wire for an open (see schematic).
3. Check BLK (238) wire for a short to
ground. If wire is OK, replace the
Seat-
4: FASTEN BELTS INDICATOR TEST
See E (PNKIBLK)
& H (BLK)
Connect: FUSED JUMPER
At: CONVENIENCE CENTER
Condition:
a Audio Alarm Assembly Removed
Connect Correct For
Between Result Diagnosis
Test Lamp
off If
the indicator response was correct, re-
place the Audio Alarm Module.
1. Checklrepair the bulb, the YEL (237)
wire, the BLK (150) wires, and the In-
strument Cluster printed circuit for
opens.
2. Check the Instrument Cluster Printed
Circuit for
a short to Battery.
E: LIGHTS-ON INPUT TEST
At: CONVENIENCE CENTER
0 Audio Alarm Module Removed

WARNINGS AND ALARMS: CHIMES
GlRGUlT OPERATION
The Warnings and Alarms System sounds a
chime to bring attention to one or more of
several conditions. These conditions are:
1) the
lights are on and the Ignition Switch is not in
RUN, BULB TEST, or START;
2) the Igni-
tion key is in the Ignition Switch when the
driver's door is open; and
3) the seatbelt is un-
buckled when the Ignition Switch is in RUN,
BULB TEST, or START.
Voltage is applied at all times through the
STOP
HAZ Fuse to terminal B, to power the
solid state Audio Alarm Assembly.
IGNITION KEY VVARNING
Voltage is applied to the Audio Alarm As-
sembly by the STOP HAZ Fuse. Whenever the
key is in the Ignition Switch and the Ignition
Switch is in LOCK, OFF, or ACCY with the
driver's door open, terminal C of the module is
grounded. This sounds the alarm.
LIGHTS-ON WARNING
When the Light Switch is in HEAD or
PARK, voltage
is applied to the Audio Alarm
Assembly. When the Ignition Switch
is in
RUN, BULB TEST, or START, voltage is
applied through the Gages Fuse to the module.
These two voltages are sensed and the alarm is
not sounded.
When the Ignition Switch is not in RUN,
BULB TEST, or START, the Gages Fuse loses
voltage. The Audio Alarm Assembly senses the
change. If voltage is still available from the
Light Switch, the Lights-On Warning alarm
will sound. The alarm can be turned off by
turning the Light Switch to the OFF setting.
The module no longer senses voltage from the
Light Switch, so the alarm does not sound.
SEATBELT WARNING
With the Ignition Switch in RUN, BULB
TEST, or START, voltage is applied through
the Gages Fuse to the Audio Alarm Assembly.
With the driver's
seatbelt unbuckled, terminal
H of the module is grounded through the Seat-
belt Switch. The FASTEN BELTS Indicator
always goes on for about
5 seconds when the
Ignition Switch is set to RUN, BULB TEST,
or START. The Fasten Belts Chime, however,
only sounds if the
seatbelt is unbuckled and
the Ignition Switch
is in RUN, BULB TEST
or START