1988 PONTIAC FIERO light

TROUBLESHOOTING HINTS
STARTER
Try the following checks before doing
the Sys-
tem Diagnosis
.
1 . Check the hydrometer eye that is built into
the vehicle Battery before troubleshooting
the Starter System
.
. Green eye . Battery is charged .
. Dark eye . Battery is discharged . Recharge
Battery
.
- Clear or yellow eye . Battery fluid is low .
Replace Battery .
2 . Check that the Starter Solenoid te
and B and battery
connections are clean and
tight
.
3 . Check that grounds 6100 and 6103 are
clean and tight
.
Go to System Diagnosis for diagnostic tests .
SYSTEM DIAGNOSIS
STARTER
NOTE:
The following tests are designed for
engines and batteries at normal operat-
ing temperatures and assumes that
there are no engine symptoms which
could cause a no start condition
. To use
the tests under other conditions could
result in misdiagnosis
.
Diagnostic steps for the symptorns listed in
the following table are listed after the table
.
COMPONENT LOCATION Page-Figure
Clutch Start Switch
.............. Above clutch pedal. on clutch pedal support
Fusible Link A (VIN E)
........... Lower RH side of engine. at Starter Solenoid .... 201- 2-A
Fusible Link A (VIN F) (VIN
8) ..... Lower RH side of engine. at Starter Solenoid .... 201- 6-B
Fusible Link A (VIN S)
............ Lower RH side of engine. at Starter Solenoid .... 201- 1-A
Fusible Link B (VIN
E) ............ Lower RH side of engine. at Starter Solenoid .... 201- 2-A
Fusible Link
B (VIN F) (VIN 8) ..... Lower RH side of engine. at Starter Solenoid .... 201- 6-B
Fusible Link B (VIN S)
............ Lower RH side of engine. at Starter Solenoid .... 201- 1-A
Fusible Link
H (VIN E) ........... RN front of engine compartment. at Junction
................................... Block 201- 3-B
Fusible Link
H (VIN F) (VIN 8) ..... LH front of engine compartment. behind battery 201- 5-C
Fusible
Link H (VIN S) ............ Lower RH side of engine. at Starter Solenoid .... 201- 1-A
Fusible Link
J (VIN E) ............ Lower RH side of engine. at Starter Solenoid .... 201- 2-A
Fusible Link
J (VIN F) (VIN 8) ..... Lower RH side of engine. at Starter Solenoid .... 201- 6-B
Fusible Link
K .................. RH front of engine compartment. at Junction
................................... Block 201- 3-B
Gear Selector Switch
............. In console. at base of gear selector ............ 201-11-E
Ignition Switch
.................. Behind IIP. on top side of steering column ...... 201- 9-A
In-Line Fuse (VIN E)
............. RH inner fender panel by battery ............. 201- 3-B
In-Line Fuse (VIN F)(VIN 8) ....... On LN side of radiator support. forward of
battery
................................. 201- 5-C
Junction Block
.................. RH front of engine compartment. behind
headlight
................................ 201- 1-A
Starter Solenoid (VIN
E) .......... Lower RH side of engine .................... 201- 2-A
Starter Solenoid (VIN F) (VIN
8) .... Lower RH side of engine .................... 201- 6-B
Starter Solenoid (VIN S)
.......... Lower RH side of engine .................... 201- 1-A
el00 (42 cavities) ................ LH front of dash. left of brake master cylinder .. 201- 0-A
Clll(1 cavity) ................... Behind battery. near positive battery cable ..... 201- 7-A
el12 (1 cavity) ................... Behind battery. near positive battery cable ..... 201- 7-A
G100 (VIN E) ................... RH front of engine ......................... 201- 4-B
G100 (VIN F) (VIN 8) ............. Lower LH front of engine .................... 201- 8-B
6100 (VIN S) .................... Lower LH front of engine .................... 201- 1-B
6103 (Except VIN
E) ............. On radiator support. behind LH headlights ..... 201-16-A
6103 (VIN
E) ................... RH inner fender panel. near battery ........... 201- 3-B
S200
........................... IIP harness. behind LH side of IIP ............ 201-10-A

STARTER AND CHARGING SYSTEM
TROUBLESHOOTING HINTS
CHARGING
* Try the following checks before doing the Sys-
tem Diagnosis
.
1 . Check the hydrometer eye that is built into
the vehicle Battery before troubleshooting
the Charging System
.
- Green eye . Battery is charged .
. Dark eye . Battery is discharged . Recharge
Battery
.
- Clear or yellow eye . Battery fluid is low .
Replace Battery .
2 . Check the Generator Belt .
3 . Check that the Starter Solenoid terminal B
and battery connections are clean and tight
.
4 . Check that the Generator connector is tight
and that the Generator battery terminal is
clean and tight
.
5 . Check the vehicle voltmeter (if equipped) to
assure accurate voltage readings
.
6 . Check the GAGES Fuse . This check can be
done by observing the BRAKE Warning
Indicator with the Ignition Switch in RUN
and the Park Brake applied
.
7 . Check the GIN-FAN Fuse .
Go to System Diagnosis for diagnostic tests .
COMPONENT LOCATION Page-Figure
Coolant Fan Relay (VIN
E) ......... LH rear corner of engine compartment. on relay
bracket
................................. 201- 3-A
Coolant Fan Relay (VIN F) (VIN 8)
. . Front of engine compartment. RH side of
radiator support
.......................... 201- 5-A
Coolant Fan Relay (VIN S)
......... LN rear corner of engine compartment. on relay
bracket
................................. 201- 0-A
Fuel Pump In-Line Fuse
........... RH side of engine compartment. on inner fender
panel
................................... 201- 1-A
Fuse Block
...................... Behind LN side of IIP. below light switch ....... 201-10-A
Fusible Link H (VIN E)
........... RH front of engine compartment. at Junction
................................... Block 201- 3-B
Fusible Link
H (VIN S) ............ Lower RN side of engine. at Starter Solenoid .... 201- 1-A
Fusible Link
J (VIN E) ............ Lower RH side of engine. at Starter Solenoid .... 201- 2-A
Fusible Link
J (VIN F) (VIN 8) ..... Lower RH side of engine. at Starter Solenoid .... 201- 6-B
Fusible Link
J (VIN S) ............ RH side of radiator support. at Junction Block .. 201- 1-A
Fusible Link
K .................. RH front of engine compartment. at Junction
................................... Block 201- 3-B
In-Line Fuse (VIN E)
............. RH inner fender panel by battery ............. 201- 3-B
In-Line Fuse (VIN
F)(VIN 8) ....... On LH side of radiator support. forward of
................................. battery 201- 5-6
.................. Junction Block RH
front of engine compartment. behind
................................ headlight 201- 1-A
........ Mass Air Flow In-Line Fuse RR side of engine compartment. on inner fender
................................... panel 201- 1-A
Starter Solenoid (VIN E)
.......... Lower RH side of engine .................... 201- 2-A
Starter Solenoid (VIN F) (VIN
8) .... Lower RH side of engine .................... 201- 6-B
Starter Solenoid (VIN S)
.......... Lower RN side of engine .................... 201- 1-A
el00 (42 cavities) ................ LH front of dash. left of brake master cylinder .. 201- 0-A
C207 (15 cavities)
................ Behind RH side of IIP. near ECM ............. 201-13-A
G100 (VIN E) ................... RH front of engine ......................... 201- 4-B
G100 (VIN F) (VIN 8) ............. Lower LH front of engine .................... 201- 8-B
G100 (VIN S) .................... Lower LH front of engine .................... 201- 1-B
6103 (Except VIN E) ............. On radiator support. behind LH headlights ..... 201-16-A
6.103 (VIN E) ................... RH inner fender panel. near battery ........... 201- 3-B
S204
........................... IIP harness. behind instrument cluster ......... 201-10-A
S206 (VIN
E) .................... Engine harness. RH front of dash ............. 201- 2-A
(Continued on facing page)

COOLANT FAN I g
TROUBLESHOOTING HINTS
@ Try the following checks before doing the Sys-
tem Check.
1. Check the CIH-FAN Fuse if the Coolant Fan
does not run.
2. Check that ground 6112 (V6 VIN S), 6117
(V8 VIN E) or 6104 (V8 VIN F and V8 VIN
8) is clean and tight.
3. Check the Fusible Link (see schematic).
4.
If the Coolant Fan runs with the Ignition
Switch OFF, replace the Coolant Fan Relay.
@ Go to System Check for a guide to normal
operation.
Go to System Diagnosis for diagnostic tests.
SYSTEM CHECK
Use the System Checlc Table as a guide to
normal operation.
SYSTEM CHECK TABLE
I ACTION I NORMALRESULT 1
COMPONENT LOCATION Page-Figure
Assembly Line Diagnostic Link
(ALDL) Connector .............. On bottom of IIP hush panel, to right of steering
column
Auxiliary Coolant Fan Relay
....... RH front side of engine compartment. ......... 201- 5-A
Auxiliary Coolant Fan Switch
...... Lower RN rear of engine .................... 201- 6-A
Coolant Fan Relay (VIN
E). ........ LH rear corner of engine compartment, on relay
bracket
................................. 201- 3-A
Coolant Fan Relay (VIN F) (VIN 8)
. . Front of engine compartment, RN side of
radiator support.
......................... 201- 5-A
Coolant Fan Relay (VIN S)
......... LH rear corner of engine compartment, on relay
................................. bracket 201- 0-A
Coolant Fan Switch
.............. Lower RH rear of engine, above starter solenoid . 201- 4-A
Coolant Temperature Sensor (VIN F)
(VIN 8).
....................... Top LW front of engine. ..................... 201- 8-C
Coolant Temperature Sensor (VIN S) Top LH front of intake manifold.
............. 201- 0-A
Electronic Control Module (ECM)
... Behind RN side of IIP ...................... 201-12-B
Fan Pressure Switch (VIN F) (VIN 8) Lower RH side of engine, on
AIC line .......... 201- 5-A
Fan Pressure Switch (VIN S)
....... Lower RN front of engine compartment, on AIC
line .................................... 201- 1-A
Fuse Block.
..................... Behind LN side of IIP, below light switch. ...... 201-10-A
Fusible Link
N (VIN E) ........... RH front of engine compartment, at Junction
Block ................................... 201- 3-B
Fusible Link N (VIN F) (VIN 8).
.... LN front of engine compartment, behind battery 201- 5-C
Fusible Link
J (VIN S) ............ RN side of radiator support, at Junction Block .. 201- 1-A
Redundant Cooling Fan Switch.
.... Top RW rear of engine ...................... 201- 1-6
C102 (4 cavities) ................. Center front of dash. ....................... 201-14-A
6104 (6 cavities)
................. Front of engine compartment, RH side of
................................ radiator. 201- 5-A
C204 (4 cavities) ................. Above LH rear corner of engine .............. 201- 0-A
C207 (15 cavities)
................ Behind RH side of IIP, near ECM ............. ,201-13-A
C224 (6 cavities) ................. Center of IIP, behind AIC control ............. 201-14-B
6104
.......................... On radiator support, behind RN headlights. .... 201-16-A
6112 (VIN E)
................... Rear of LN cylinder head. ................... 201- 3-C
6112 (VIN S)
.................... Rear of LH cylinder head. ................... 201- 0-C
6118 (VIN F) (VIN 8)
............. Rear of RH cylinder head. ................... 201- 5-A
6118 (VIN S)
.................... Rear of RH cylinder head. ................... 201- 1-C
(Continued on next page)
With
the engine cold
and idling, turn the
AIC Selector to
NORM (if equipped
with Ale)
VIN E: Coolant Fan
turns on
VIN S, VIN
F &
VIN 8: Coolant Fan
(and Auxiliary
Coolant Fan-if
equipped) turns on
when
A/C Control
Head Pressure
exceeds 233 psi
(1600
kPa)
(Continued on next page)

COOLANT FAN
With the engine
warm, run the
engine at a fast idle
for several minutes
(Continued
from previous page)
Switch to off
With
the engine
coolant below
operating
temperature, move
the AlC Selector to
OFF
Coolant Fan (and
Auxiliary Coolant
Fan-if equipped)
turns on before the
Coolant
Temperature
Indicator in the
Instrument Panel
lights or before the
Coolant
Temperature Gage
needle indicates hot
Coolant Fan (and
Auxiliary Coolant
Fan-if equipped)
turns off
VIN E:
Coolant Fan
turns off
VIN S, VIN F
&
VIN 8: coolant Fan
(and ~~~ili~~~
Coolant Fan-if
equipped) turns off
when
A/C Control
Head Pressure falls
below 233 psi (1600
kPa)
- -
* Refer to System Diagnosis when a result is not
normal.
SYSTEM DIAGNOSIS
V6 VIN S
* Do the tests listed for your symptom in the
Symptom Table below.
@ Tests follow the Symptom Table.
COMPONENT LOCATION Page-Figure
.......................... ............ 6-200 Behind IIP, left of steering column 201-10-A
....... .................... S104 (VIN S) Engine harness,
lower RN side of engine 201- l-A
....... .......................... S108. Engine harness, lower RN side of engine .201- 5-A
........................... S111 Engine harness, RR rear of engine compartment 201- l-A
.......................... S126. Engine harness, RR rear corner of engine
............................ compartment 201- 5-A
.......................... ............ S127. Engine harness, RH front of dash. 201- 2-A
.......................... S128. Cooling Fan harness, RN front corner of engine
............................ compartment 201- 6-A
.................... S142 (VIN S) Engine harness, lower RR side of engine ....... 201- l-A
............ S143 (VIN F) (VIN 8) ............. Engine harness, RH front of dash. 201- 6-A
.................... S143 (VIN S) Engine
harness, center front of dash. .......... 201- l-A
.......................... S158. Engine harness, behind RH side of IIP
.......................... S205. I/P harness, behind instrument cluster. ........ 201-10-A
S206 (VIN E)
.................... Engine harness, RH front of dash. ............ 201- 2-A
S206 (VIN
F)(VIN 8). ............. Engine harness, top center rear of engine. ...... 201- 7-A
.................... S206 (VIN S) Engine harness, above rear of engine .......... 201- 1-A
SYMPTOM TABLE
all times with the
engine cool and the
SYMPTOM
Coolant Fan does
not
run at all
Coolant Fan does
not run with engine
hot but does
run
with the A/C on
(Continued on next page)
FOR DIAGNOSIS
Do Test A
Do Test B

COOLANT FAN 1:
0 If the result is correct, go to section 6E for
ECM diagnosis.
1. Go to Table 2
A: COOLANT FAN OPEN TEST
(TABLE
1 )
Connect: FUSED JUMPER
At: ALDL CONNECTOR
Condition:
@ lgnition Switch: RUN
A: COOLANT FAN OPEN TEST
(TABLE
2)
At: COOLANT FAN RELAY CONNECTOR
(Connected)
Condition:
0 lgnition Switch: RUN
Connect
Between
B & Ground
Jumper Correct Result For Diagnosis
Between
(DK GRN/ Coolant Fan
WHT) & See 1
1 Ground 1 runs 1 1
Correct Result
Coolant Fan
runs
If the Coolant Fan runs, check the DK
GRNIWNT (335) wire for an open. If the
wire is OK, go to section 6E for ECM
diagnosis.
1. Go to Table 3.
For Diagnosis
See 1
A: COOLANT FAN OPEN TEST
(TABLE
3)
Connect: TEST LAMP
At: COOLANT FAN RELAY CONNECTOR
(Disconnected)
Condition:
0 lgnition Switch: RUN
Connect Correct Result For Diagnosis
Between
lights
0 If the results are correct, go to Table 4.
1. Check CIN-FAN Fuse and BRN (250) wire
for open.
2. Check Fusible Link J and RED (2) wire for
opens.
A: COOLANT FAN OPEN TEST
(TABLE
4)
Connect: FUSED JUMPER
At: COOLANT FAN RELAY CONNECTOR
(Disconnected)
Jumper Correct Result For Diagnosis
Between
(BLKIRED)
If the Coolant Fan runs, replace the
Coolant Fan Relay.
1. Leave fused jumper in place and go to
I Table 5.
A: COOLANT FAN OPEN TEST
(TABLE
5)
B: COOLANT FAN SWITCH TEST
Connect: TEST LAMP
At: COOLANT FAN CONNECTOR
(Disconnected)
Condition:
Fused jumper from Table
4 connected
Connect
Between
B (BLKIRED)
& Ground
B (BLKIRED)
& A (BLK)
Connect: FUSED JUMPER
At; REDUNDANT COOLING FAN
SWITCH
CONNECTOR (Disconnected)
Condition:
@ lgnition Switch: RUN
If the results are correct, replace the
Coolant Fan.
1. Check BLKIRED (532) wire for an open.
2. Check BLK (150) wire for an open.
Correct Result
Test Lamp
lights
Test Lamp lights
Jumper
Between
WHT &
Ground
For Diagnosis
See 1
See 2
@ If the Coolant Fan runs, replace the
Redundant Cooling Fan Switch, then
refer to Section 6E for ECM diagnosis.
1. Check the DK GRNIWNT (335) wire for
an open (see schematic).
Correct Result
Coolant Fan
runs
For Diagnosis
See 1

COOLANT FAN rn
6: COOLANT FAN SHORT TEST
1. With the Ignition Switch in RUN, remove
the Redundant Cooling Fan Switch connec-
tor.
If the Coolant Fan does not turn off, go to
Step
2.
If the Coolant Fan turns off, replace the
Redundant Cooling Fan Switch.
2. Remove the CIR-FAN Fuse.
If the Coolant Fan turns off, check the DK
GRNIWHT
(335) wires for a short to ground.
Refer to Section 6E for ECM diagnosis if the
wires are OK.
a If the Coolant Fan does not turn off, replace
the Coolant Fan Relay.
SYSTEM DlAGNOSlS
V8 VIN F AND V8 VIN 8
Do the tests listed for your symptom in the
Symptom Table below.
Tests follow the Symptom Table.
SYMPTOM TABLE
I SYMPTOM I FORDIAGNOSIS I
I Do Test A I
I not run at aB I I
Coolant Fan runs at
all times with the
A/C off and engine
cool
(Continued in next column)
Do
Test
B
Auxiliary Coolant
Fan does not run at
all
:Continued from previous column)
Fan runs at
all times
with
AIC off and the
Do Test C (Continued
from previous column)
GRNIWNT
(335) wire for an open. If wire
is OK, go to Section 6E for ECM diag-
nosis.
1. Go to Table 3.
A: COOLANT FAN OPEN TEST
(TABLE
1)
At: ALDL CONNECTOR
Condition:
I B &Ground I I See l' I
Connect
Between
If the result is correct, go to Section 6E
for ECM diagnosis.
A: COOLANT FAN OPEN TEST (TABLE
2)
Correct Result
I
Connect: FUSED JUMPER
At: COOLANT FAN RELAY CONNECTOR For
Diagnosis
(Connected)
Condition: lgnition Switch: RUN
Jumper
I Correct Result I For Diagnosis I Between
(DK GRN1 Coolant Fan
WHT) & See 1
1 Ground 1 runs 1 1
A: COOLANT FAN OPEN TEST (TABLE
3) I
Connect: TEST LAMP
At: COOLANT FAN RELAY CONNECTOR
(Disconnected)
Condition:
Connect I Correct Rewn I For Diagnosis I I Between
C (BRN) &
Ground
If the results are correct, go to Table
4.
1. Check CIH-FAN Fuse and BRN (250) wire
for opens.
2. Check Fusible Link H and ORN (440) wire
for opens.
E (ORN)
&
Ground
(Continued in next column)
(Continued on next page)
Test Lamp
lights See
1
Test
Lamp
lights See 2

COOLANT FAN
0 If the Coolant Fan runs, replace the
Coolant Fan Relay.
A: COOLANT FAN OPEN TEST (TABLE
4)
Connect: FUSED JUMPER
At: COOLANT FAN RELAY CONNECTOR
(Disconnected)
1. Leave fused jumper in place and go to
Table
5.
A: COOLANT FAN OPEN TEST (TABLE
5 1
Connect: TEST LAMP
At: COOLANT FAN CONNECTOR
(Disconnected)
Condition:
0 Fused jurnper in place from Table 4
For Diagnosis
See 1
Jumper
Between
E (ORN) & A
(BLKIRED)
Connect Correct Result For Diagnosis
Betvveen Correct
Result
coolant an
runs
B (BLKIRED) Test Lamp
1 & Ground 1 lights I See1
B (BLKIRED) Test Lamp
& A (BLK) I lights
If the results are correct, replace the
Coolant Fan.
1. Check BLKIRED (532) wire for an open.
2. Check BLK (150) wire for an open.
B: COOLANT FAN SHORT TEST 6: AUXILIARY COOLANT FAN OPEN
With the Ignition Switch in RUN, remove TEST (TABLE 2)
the CIH-FAN Fuse.
0 If the Coolant Fan turns off, check the DK
GRNIWNT (335) wire for a short to ground.
If the wire is OK, refer to Section 6E for
ECM diagnosis.
If the Coolant Fan does not turn off, replace
the Coolant Fan Relay.
6: AUXILIARY COOLANT FAN OPEN
TEST (TABLE
1)
Connect: FUSED JUMPER
At: AUXILIARY COOLANT FAN RELAY
CONNECTOR (Connected)
Condition:
0 Ianition Switch: RUN Connect:
TEST LAMP
At: AUXILIARY COOLANT
FAN RELAY
CONNECTOR (Disconnected)
Condition: Ignition Switch: RUN
Connect
Between
D (ORN) &
Ground
E (ORN)
&
Ground
Jumper
Between
If the Auxiliary Coolant Fan runs, check
the DK
GRNlWNT (935) and GRY (731)
wires for opens. If wires are good, check
switches.
1. Go to Table 2.
F (DK GRNl
WHT) &
Ground If
the results are correct, go to Table
3.
1. Check ORN (440) and BRN (250) wires for
opens.
2. Check ORN
(440) wires for opens.
Correct Result
Test Lamp
lights
Test Lamp lights
Correct Result For
Diagnosis
See 1
See 2
Auxiliary
Coolant Fan
runs
Connect: FUSED JUMPER
At: AUXILIARY COOLANT FAN RELAY
CONNECTOR (Disconnected)
For
Diagnosis See 1
Jumper
Between
(ORN' & A
(BLKIRED)
6: AUXILIARY COOLANT FAN OPEN
0 If the Auxiliary Coolant Fan runs, replace
the Auxiliary Coolant Fan Relay.
1. Leave fused jumper in place and go to
Table
5.
Correct Result
Auxiliary
Coolant Fan
runs
For Diagnosis
See 1

COOLANT FAN
C: AUXILIARY COOLANT FAN OPEN
TEST (TABLE
41
At: AUXILIARY COOLANT FAN CONNECTOR
(Disconnected)
iliary Coolant Fan.
1. Check BLKIRED (932) wire for an open.
2. Check BLK (150) wire for an open.
D: AUXILIARY COOLANT FAN SHORT
TEST
1. With the Ignition Switch in RUN, discon-
nect the Auxiliary Coolant Fan Switch.
If the Auxiliary Coolant Fan does not turn
off, go to Step
2.
If the Auxiliary Coolant Fan turns off,
replace the Auxiliary Coolant Fan Switch.
2. Disconnect the Fan Pressure Switch.
If the Auxiliary Coolant Fan does not turn
off, go to Step
3.
* If the Auxiliary Coolant Fan turns off,
replace the Fan Pressure Switch.
3. Remove the CIN-FAN Fuse. A: COOLANT FAN OPEN TEST
y Coolant Fan does not turn (TABLE 1 )
Auxiliary Coolant Fan Relay.
Coolant Fan turns off, check
the DK
GRNIWRT (935) and GRY (731)
wires for a short to ground.
SYSTEM DIAGNOSIS
V8 VIN E
Do the tests listed for your symptom in the
Symptom Table below.
* Tests follow the Symptom Table.
SYMPTOM TABLE
but does run with
At: COOLANT FAN RELAY CONNECTOR
A: COOLANT FAN OPEN TEST (TABLE
2)
Connect: TEST LAMP
At: COOLANT FAN RELAY CONNECTOR
(Disconnected)
Condition:
Ignition Switch: RUN
Connect
Between
I Conen Resun I For Diagnosis I
Ground lights
* If the results are correct, go to Table 3.
1. Check CIK-FAN Fuse and BRN (250) wire
for opens.
2. Check Fusible Link H and RED (2) wire
(Continued on next page)