1988 PONTIAC FIERO heater

Adjust 2 . Filler panel 3 . Electrical connector
1 . Increase Current - Turn adjusting screw 4 . ~~l~/~~~~~
clockwise 5 . Horn
2 . Decrease Current . Turn adjusting screw
counterclockwise
Install or Connect
3 . Current adjustments should be made 1/4 turn
(90") at a time
Horn Assembly
Remove or Disconnect
1 . Six screws from filler panel behind front fascia on
driver's side 1
. Horn
2 . Bolt/screw
3 . Electrical connector
4
. Filler panel
5 . Six screws
Horn Relay
The horn relay is in the convenience center.
behind the instrument panel to the right of the steering
column
. To remove the relay. pull it straight out .
REPLACEMENT LIGHT BULBS
For exterior light replacement procedures. see the rest of this
section
. For interior light replacement procedures. see Section $A
and Section 8C .
EXTERIOR LIGHTS Trade No . ...................................................................................................................... Back-up Lights 1 156
Center
High-Mounted Stoplight ............................................................................................. 577
Front Barking/Turn Signal Eights ..................................................................................... 2057
Fog Lights
............................................................................................................................... H-3
Headlights ....................................................................................................................... H6054 ................................................................................................................ License Plate Lights 194
.................................................................................... Rear Tail/Stop/Turn Signal Lights 2057
Sidemarker Lights (Front and Rear) ...................................................................................... 194 ..................................................................................................................... Underhood Light 211
BNTERBOR LIGHTS Trade No .
......................................................................................... Air Conditioner/Heater Controls 194 .................................................................................................................. Ashtray & Lighter 194 .............................................................................................................. Cargo Compartment 561
................................................................................................ Cluster & Speedometer (Tach) 194 ..................................................................................................................... Console Ashtray 194 ............................................................................................................. Console Compartment 194
Courtesy Lights
..................................................................................................................... 194 ......................................................................................................................... Dome Light 561
Gear Selector Indicator
............................................................................................................ 74 .......................................................................................... Headlight High-Beam Indicator 194
Indicator Lights
..................................................................................................... Brake System Warning 194
With Gages
........................................................................................................................ 74
............................................................... Charging System Warning (except Rally Gages) 194 .................................................................................................................... Choke Warning
194
With Gages
........................................................................................................................ 74
...................................................................... Oil Pressure Warning (except Rally Gages) 194 ............................................................................................................ Seat Belt
Reminder 194
With Gages
.................................... ... ................................................................................. 74 ............................................................................................. Service Engine Soon Warning 194
With Gages
..................................................................................................................... 74 ............................................................ Temperature Gage Warning (except Rally Gages) 194
........................................................................................................................ Reading
Light 906 ............................................................................................................ Turn Signal Indicators 194

INSTRUMENT PANEL, GAGES & CONSOLE 8C-'I
SECTION 8C
NSTRUMENT PANEL, GAGES & CONSOLE
CONTENTS
General Description ................................... 8C-1
Instrument Panel and Gages ........................ 8C-1
Printed Circuit .......................................... 8C-1
Instruments ................................................... 8C- 1
Speed Sensors
............................ .. ............. 8C- 1
Pinion Gear
............................................. 8C-2
Photo Speed Sensor ................................ 8C-2
PM Generator ................... .. ...... ............... 8C-2
Speedometer ................................................ 8C-2
Mechanical ....................... .. .................... 8C-2
Quartz ........................ .. .......................... 8C-2
Digital .................... .. ...... ................. 8C-2
Fuel Gage .................................................... 8C-2
Temperature Warning Light ...................... 8C-3
Generator Warning Light ............................ 8C-3
Engine Oil Pressure Light ............................ 8C-3
"Service Engine Soon" Light ....................... 8C-3
Upshift Indicator Light .............................. 8C-3
Diagnosis .................... .. ........................... 8C-3
General Information .................................. 8C-3
Instrument Panel & Gages ...................... ..... 8C-3
On-Car Service ......................... .. ........... 8C-4
Instrument Panel Pad ................................... 8C-4
Instrument Panel Cluster ........................... 8C-4
Instrument Panel Carrier ............................. 8C-4
Headlight Switch .......................................... 8C-4
Console Mounted Switches and
Accessories
............................................... 8C-4
Console ......................................................... 8C-4
Speedometer .................................................. 8C-5
Illustra3ions ................................................. 8C-5
IP Pad ........................................................... 8C-5
IP Carrier ................................................... 8C-6
Instrument Cluster ....................................... 8C-6
Lower IP Covers ......................................... 8C-7
IP Trimplates ............................................... 8C-7
IP Hush Panels; with A/C .......................... 8C-8
..................... IP Lower Trim Pad (Console) 8C-8
Map Holder or Map Pocket ........................ 8C-8
IP Hush Panels; without A/C ..................... 8C-9
Radio Mounting ........................................... 8C-9
Subwoofer & Hatch Release
Switches/Covers ........................................ 8C- 10
Foglamp Switch/Cover ................................ 8C- 10
Oil Pressure and Temperature
Switches
..................................................... 8C-11
Heater/Ventilation/Defroster
Ductwork .................................................. 8C- 12
A/C and Defroster Ductwork ..................... 8C-13
Ram Vent System Ductwork ....................... 8C-14
Console Mounted Switches
&
Accessories ................................................. 8C- 14
Dash Insulators
............................................ 8C- 15
Heater Floor Outlet
..................................... 8C-15
................ Headlamp/Parking Lamp Switch 8C- 15
............. Dash Mounted Accessory Switches 8C- 15
GENERAL DESCRIPTION
INSTRUMENT PANEL AND GAGES
INSTRUMENTS
Instruments consist of fuel gage, temperature
The instrument panel on most cars is a sing,e unit indicator light, generator light, oil pressure indicator
design and all parts attach to the main instrument light, and speedometer. See Section 9F for optional
panel with clips and screws. To service the instrument Gages and tachometer. Service on instruments
panel and components see on-car service information, can be obtained through authorized repair stations.
However, knowledge of instrument circuit checks will
PRINTED CIRCUIT
All models are equipped with printed circuits
which supply current to most instrument panel lights
and instruments. These circuits are made of copper foil
which is die cut and bonded to a polyester base film
(usually mylar). The printed circuit electrical power is
supplied by a connector containing several wires, as
shown in the instrument panel wiring harness
installation instructions. The connector also helps
retain the printed circuit to the speedo cluster. The rest
of the circuit is retained by additional connectors (if
used) and snap-in
bulbs/sockets. For individual
printed circuit diagrams, see Section
8A-80/8 1/82/83,
'Instrument Panel'. help
in determining if operating difficulties lie in the
instrument itself or its related circuit.
Instruments have been designed for easy removal
by elimination of separate wiring. With the wiring
provisions integrated with the instrument panel wiring,
the instruments can be removed after removing the
trim and lens.
SPEED SENSORS
There are three speed sensors currently in use:
1. PINION GEAR; used in mechanical systems
2. PHOTO SPEED SENSORS; used in mechanical
systems
3. PM GENERATOR; used in electronic systems

INSTRUMENT PANEL. GAGES & CONSOLE 8C-3
tank only when ignition switch is turned to "ON" or
"ACCESSORY" positions.
When ignition is turned to "OFF" or "START"
positions, the pointer may come to rest at any position.
The letters
"E" and "F" on the fuel gage are used to
point out direction of indicator travel only.
TEMPERATURE WARNING LIGHT
The engine temperature warning light is
controlled by a thermal switch which senses engine
coolant temperatures.
When the ignition switch is turned to "START"
position, a test circuit is closed and the light will come
on to indicate whether the light is functioning properly.
It is important to note that with low boiling-point
coolants (such as plain water) the temperature light
may not come on even though the coolant is boiling.
GENERATOR WARNING LIGHT
The generator warning light, located in the
instrument cluster, should come on when the ignition
switch is turned
"ON" and engine is not running. If
not, either the bulb is burned out or wiring to generator
has an open circuit.
When the generator voltage output becomes
greater than the battery voltage, the
"GEN" light
should go out. This does not, however, indicate
whether the battery is being charged or if the voltage
regulator is functioning properly.
Checks of the charging system are covered in
Section 6D, 'Engine Electrical'.
ENGINE OIL PRESSURE LIGHT
The engine oil pressure warning light is mounted
in the instrument cluster and controlled by a pressure
operated switch located on the engine block. When the ignition switch is
in the
"run" or "start9' position, the
oil pressure light should come on. If not, the bulb is
burned out, there is an open circuit between the bulb
and the oil pressure switch, or there is an open circuit
between the oil pressure switch and the choke heater.
After the engine is running, the oil pressure light
should go out when the oil pressure reaches the correct
specification. If not an oil pressure problem, a faulty oil
pressure switch or an open circuit from the choke
heater fuse to the oil pressure switch is indicated.
"SERVICE ENGINE SOON" LIGHT
All cars have a "SERVICE ENGINE SOON"
light mounted in the instrument cluster. The
"SERVICE ENGINE SOON9' light should come on
during engine starting. The light may stay on
a short
time after the engine starts.
If the light comes on while
driving, service to the emission control system may be
required. See Section
6E and Section 8A-80,
'Instrument Cluster', for complete diagnosis and
wiring diagrams of the
""P;RVICE ENGINE SOON"
light circuit.
UPSHIFT INDICATOR LIGHT
If your vehicle has a manual transmission, there
may be an
''Upshift" light on the instrument panel.
This light is illuminated to indicate optimum shift
points throughout the range from optimum fuel
economy to optimum performance. When this light is
on, shift your transmission to the next higher gear
range if conditions permit. For fuel economy,
accelerate slowly and shift when the light goes on. For
performance, accelerate as desired and shift when the
light goes on.
Safe operation of the vehicle may require shifting
differently than indicated by the "Upshift" light to
adapt to weather, road or traffic conditions.
Downshifting one or more gears may be required
to keep the engine running smoothly or to maintain
satisfactory performance.
DIAGNOSIS
Diagnostic information for all instrument panel
electrical systems is found in Section
8A-80,
'Instrument Panel'.
CAUTION: When removing or
installing any electrical units,
disconnect the negative battery cable
to prevent possible short circuits
which could lead to personal injury
and/or property damage. When
replacing a speedometer or
odometer assembly, the law requires the
odometer reading of the replacement unit to
be set to register the same mileage as the
prior odometer.
if the same mileage cannot be
set, the
law requires that the replacement
odometer be set to zero and a label be
installed on the driver's door frame to show
the previous odometer reading and the date
of replacement.
GENERAL BNFORMATlOM
INSTRUMENT PANEL AND GAGES
The instrument panel is a single unit design and
and screws. To service the instrument panel and
all parts attach to the main instrument panel with clips components see Figs. 601 through 610.

8C.4 INSTRUMENT PANEL, GAGES & CONSOLE
ON-CAR SERVlCE
lNSTRUMEMT PANEL PAD
Figure 601
Remove or Disconnect
1. Four (4) screws in defroster ducts.
2. Screws
under lip of
I.P, pad.
3. I.P. pad from carrier.
lnstall or Connect
1. I.P. to carrier.
2. Screws
under lip of I.P. pad.
3. Four (4) screws in defroster ducts.
INSTRUMENT PANEL CLUSTER
Figure 683
Remove or Disconnect
1. Right and left lower trim plates. Removal of
lower I.P. covers not required.
2. Instrument cluster trim plate.
3. Six (6) cluster attachment screws, pull cluster
back and disconnect speedo cable and electrical
connections.
4. Trip odometer, reset knob (if so equipped) and
remove cluster lens.
5. Individual gages and/or speedo head are now
accessible for service or replacement. If service is
intended for only gages or tachometer, skip Step
3.
Install or Connect
1. Trip odometer, reset knob (if so equipped) and
remove cluster lens.
2. Six
(6) cluster attachment screws, pull cluster
back and disconnect speedo cable and electrical
connections.
3. Instrument cluster trim plate.
4. Right and left lower trim plates. Removal of
lower I.P. covers not required.
INSTRUMENT PANEL CARRIER
Figure 602
Remove or Disconnect
Negative battery cable.
Console. Instrument panel pad and lower hush panels.
Right and left lower I.P. covers and trim plates.
Instrument panel cluster and headlight switch.
Lower steering column.
Five (5) upper and six (6) lower I.P. carrier to
cowl screws.
Instrument panel electrical harness at cowl
(bulkhead) connector, and under dash.
I.P. carrier from car.
10. I.P. mounted components (A/C, defroster ducts,
wiring harness, etc.) are now accessible for service
or replacement.
11. Any seals or sealant damaged during
disassembly.
Install or Connect
I.P. carrier to car.
Instrument panel electrical harness at cowl
(bulkhead) connector, and under dash.
Five (5) upper and six (6) lower I.P. carrier to
cowl screws.
Steering column.
Instrument panel cluster and headlight switch.
Right and left lower I.P. covers and trim plates.
Instrument panel pad and lower hush panels.
Console.
Negative battery cable.
HEADLIGHT SWITCH
Figure 620
Remove or Disconnect
1. Right and left lower trim plates. Removal of
lower I.P.
cover(s) not required.
2. I.P. cluster trim plate.
3. Two (2) switch assembly retaining screws.
4. Depress side tangs and pull switch assembly from
I.P.
5. Individual switches of assembly are now
accessible for service or replacement.
Install or Connect
1. Depress side tangs and replace switch assembly
to I.P.
2. Two
(2) switch assembly retaining screws.
3. I.P. cluster trim plate.
4. Right and
left lower trim plates. Removal of
lower I.P.
cover(s) not required.
DASH MOUNTED ACCESSORY SWITCHES
Figure 62 1
Installation for various dash mounted accessory
switches is shown in Fig.
62 1.
CONSOLE MOUNTED SWITCHES AND
ACCESSORIES
Figure 6 17
Installation of various console mounted switches,
lights and accessories is shown in Figure 617.
CONSOLE
Remove or Disconnect
1. Negative battery cable.
2. Shift gate trim plate. Requires removal
of shift
handle and seven (7) screws.
3. Radio/A/C-heater controller trim plate.

INSTRUMENT PANEL, GAGES & CONSOLE 8C-5
4. A/C-heater controller (see Section 1B).
5. Radio (see Section 9A).
6. Electrical connectors (cigar lighter, ash tray light,
etc.) and pull harness forward out of console.
7. Six (6) console hold-down and two (2) console to
I.P. screws and remove console.
Install or Connect
1. Six (6) console hold-down and two (2) console to
I.P. screws and replace console.
2. Electrical connectors (cigar lighter, ash tray light,
etc.) and pull harness forward out of console.
3. Radio (see Section 9A).
4. A/C-heater controller (see Section 1B).
5. Radio/A/C-heater controller trim plate.
6. Shift gate trim plate.
7. Negative battery cable.
SPEEDOMETER
Figures 603
Remove or Disconnect
Right and left lower trim plates. Removal of
lower
I.P. cover(s) not required.
Instrument cluster trim plate.
Six (6) cluster attachment screws, pull cluster
back and disconnect speedo cable.
Cluster lens.
Two (2) screws retaining speedo head in cluster
from rear.
Electrical (VSS) connectors and remove speedo
head.
Install or Connect
Electrical (VSS) connectors and replace speedo
head.
Two (2) screws retaining speedo head in cluster
from rear.
Cluster lens.
Six (6) cluster attachment screws, reconnect
speedo cable, replace cluster.
Instrument cluster trim plate.
Right and left lower trim plates.

2-STUD, PART OF CASE ASSEMBLY
3-SEAL 7-DUCT-OTR.
AIR-R.H.
8 -DIST. ASM
4-CORE AND CASE ASSEMBLY
9-DUCT-OTR. AI R-L.H.
5-DUCT - SIDE WINDOW DEFROSTER L.H. I
Fig. 6 14 Heater/Ventilation/Defroster Ductwork

INSTRUMENT PANEL, GAGES & CONSOLE 8C-15
1 -INSULATOR (UPPER); UPPER
RETENTION IS PROVIDED BY CROSS
CAR
WIRE HARNESS CONDUIT
FASTENERS.
2- RETAINER
3- INSULATOR (LOWER)
4- BEND TAB TO RETAIN MAT
1. HEATER AND DEFROSTER ASSEMBLY
2. 1.4
N-rn (12 LBS. IN.) INSTALL FIRST
3. CONSOLE ASSEMBLY
4. 1.4
Narn (12 LBS. IN.)
5. FLOOR OUTLET ASSEMBLY
Fig. 6 19 Heater Floor Outlet
Fig. 6
18 Dash Insulators
SWITCH, HATCH SWITCH, REAR WIPER RELEASE
SCREW SWITCH, REAR DEFOG
1-BOLT/SCREW 2-HEADLAMP
Fig. 620 Headlamp/Parking Lamp Switch
- Fig. 62 1 Dash Mounted Accessory Switches

RADIO SYSTEMS AND ANTENNAS 9A-1
SECTION 9A
0 SYSTEMS AND ANTENNAS
CONTENTS
............................................. General Description .................................... 9A-1 Radio Operation 9A-4
Radio
............................................................ 9A-1 ETR AM/FM Stereo (UM-7) ....................... 9A-4
Antennas
........................................................ 9A- 1 ETR Stereo Cassette (UM-6) ......................... 9A-5
Fixed Antenna
.......................................... 9A- 1 ETR Stereo/Cassette/Eaualizer
Diagnosis ........................................................
Radio ....................... .. ................................
Static and Noise .................................... .....
........................................ Popping Noise
Preliminary Diagnostics
.............................
Antenna ................................. .. ................
Tape Player .................. .... .......................
Service Procedures ....................................
Radio and Speakers ........................... .............
Radio Noise Suppression Equipment ............
Stereo Cassette Tape Player ..........................
Tape & Tape Player Care ........................
(UX-1) ..................................................... 9A-6
Advanced ETR
Stereo/Cassette/Equalizer Touch
Control
.................................... ... .............. 9A-7
On-Car Service .............................................. 9A-9
Radio Receiver
............................................ 9A-9
Radio Steering Wheel Controls
..................... 9A-9
Audio Amplifier
........................................... 9A-9
Radio Suppression
..................................... 9A-9
Front Speaker
................................................. 9A-9
............... Rear Speaker; Sub Woofer Speaker
9A-9
Antenna
..................... .. ............................. 9A- 10
GENERAL DESCRIPUION
RADIO ANTENNAS
For radios and radio use see the "Radio Fixed Antenna
Operation" section. ETR means 'Electronically Tuned The
fixed antenna on the right front fender
Receiver'. cannot be adjusted up or down. It may provide
improved reception in rural areas.
- The fixed antenna is designed to withstand most
car washes without damage. If the antenna becomes
slightly bent, you can straighten it by hand. The
antenna can be replaced if severely bent (by vandalism,
etc.). Antennas must be kept clean for good
performance.
RADIO
Because radio problems are normally repaired at
authorized warranty repair stations, the tendency is to
remove the set when a problem is reported, without any
preliminary diagnosis. This results in a large number
of radios being "No Trouble Found" units when
received by the warranty repair stations. Often the
trouble can be corrected without radio removal. wire.
If equipped with
A/C, the blower motor has a
built-in capacitor. Extra electrical equipment added to
the static if not properly grounded or wiring was
improperly routed.
Weak
FM station reception will be affected by
nearby buildings, car speed and direction. These
"flutter" and "fading" conditions are characteristic of
weak FM signals.
ETR radios require clock and button reset if the
battery is disconnected.
Popping Noise
Static and Noise Operating devices such as turn signals, pushing in
cigarette lighter, operating stop lights, etc., may cause
Ground strap connections must be clean and
a popping noise on distant (weak) AM signals.
tight, spark plug cables must be TVRS type and in
good condition and resistance-type spark plugs used.
Preliminary Diagnostics
Capacitors are used in the generator, heating/air
conditioning system, and fuse panel to reduce noise
The inconvenience of driving without a radio
entering the radio through the feed wires. If the car has
while the set is being serviced can often be avoided if
a heater only, the capacitor is in the blower motor feed
the following quick checks are used to eliminate