1988 PONTIAC FIERO check engine

THEFT DETERRENT SYSTEM: PASSKEY
(Continued from previous page)
If engine does not
Remove hush panel
disconnect C228
( Two-cavity
connector at base of
steering column)
Attempt to
start Engine should not
engine
Reconnect C228 and
attempt to start
engine again (must
be done within two
minutes of first
attempt)
Turn Ignition
Switch to
OFF
Wait four minutes
and turn Ignition
Switch to START crank
If engine cranks, do
Starter Enable
Relay Test
in
System Diagnosis
Engine should not
crank If engine cranks,
replace PASSKEY
I Decoder Module
I Replace hush panel 1 I
SYSTEM DIAGNOSIS
Use the following table to deter
cedure to use. If engine won't crank, or cranks
but won't start, enter ECM Diagnostic Mode
and check for display of code
46.
There are four "No Start"conditions that can
occur on a vehicle equipped with PASSKEY
that may appear to be caused by PASSKEY.
The four conditions are given in the following
table. The first of these is
host certain to be a
PASSKEY problem. The second and third can
be caused by other systems on the vehicle. The
fourth symptom is definitely not related to
PASSKEY.
SYMPTOM TABLE
No Crank
ECM Code
46
Present
Crank but no Start
ECM Code
46
Present A:
Lock Cylinder
and Harness Test
B: Decoder Module
Test
D: ECM Enable Test
No ECM Code
46
does not work Indicator open
If your symptom is not one of the symptoms
listed, do all the following tests.
* Refer to System Diagnosis when a result is not
normal.

THEFT DETERRENT SYSTEM: PASSKEY I i
A: LOCK CYLINDER AND HARNESS
TEST
1. Remove the hush panel under the steering
column. Disconnect the two-cavity connec-
tor in the wire leading into the steering col-
umn. Connect the male and female parts to
the mating connectors on the pigtails from
the 535628 Interrogator or equivalent.
2. Insert the customer's ignition key into the
Ignition Switch Lock Cylinder.
3. Press the On-Off switch on the 535628 Inter-
rogator to the ON position.
* The window above the Key Code Reader
indicates the electrical code for the key
(1 to
15) or
"En error.
Rotate the ignition lock cylinder while the
key is inserted to insure that the correct code
is read in all positions.
- If the code is correct in all positions, proceed
to step 5.
- If code is not correct in all positions, replace
the Lock Cylinder.
* If the window shows "E ", proceed to step 4.
4. Check the customer's ignition key by insert-
ing it in the Key Code Reader on the 535628
Interrogator.
If the Interrogator indicates
"EM, replace
the key with a spare or follow the procedures
under Key Replacement.
If Interrogator shows the electrical code
(1
to 15), replace the Lock Cylinder. (See pro-
cedure following Key Duplication Pro-
cedure). 5.
Set the Key Code Selector on the 535628
Interrogator to the same electrical code
determined in step 3. Turn the Ignition
Switch to START.
If engine starts, reconnect vehicle wiring
and check that the two-cavity connector at
the base of the steering column mates cor-
rectly.
If engine does not start, go to Test B,
Decoder Module Test.
B: PASS KEY DECODER MODULE TEST
(TABLE
1 )
At: PASSKEY DECODER MODULE
CONNECTOR (Disconnected)
Condition:
1 . 1mition switch: START I
Ignition Switch: RUN
Continued from previous c
1. Check the PNKIBLK (439) wire and ClN
Fuse for an open.
2. Check the ORN (440) wire and VATS Fuse
for an open.
3. Check the
BLKIWT (450) wire for an
open.
4. Check the PPL (963) wire for an open.
If
wire is good, replace ECM.
5. Check DK GRN (965) wire for an open. If
wire is good, do Test C.
For Diagnosis
See 1
See 2
See 3
See 4
Measure
Between
A1 (PNKI
BLK) &
Ground
(ORN' &
Ground
A1 (PNKI
BLK)
& I31
(BLKIWNT)
A2 (PPL) &
Bl (BLKI
WNT)
B: PASSKEY DECODER MODULE TEST
Correct
Voltage
Battery
Battery
Battery
5 Volts
(TABLE 2)
Measure: RESISTANCE
At: PASSKEY DECODER MODULE
CONNECTOR (Disconnected)
Conditions: Negative Battery Terminal
Disconnected
r No lCev ln lainition Switch
Measure
- Correct For Diagnosis
Between Resistance
& open circuit
UB2 (BRN) See 1
crank,
replace the PASSKEY Decoder
Module.
-
(Continued in next column) A3 (DK GRN)
& Ground
I . If voltages are correct, go to Table 2.
(Continued in next column)
Battery See 5

Continued from previous page)
Note: VVhen the PASSKEY Decoder Module
is replaced, the new key code may not
match the code in the owner's existing
keys. If it does not match, then new
keys must be made. Use the key
duplication procedure.
1. Check YEL (921) and BRN (922) wires for
shorts to ground or between the two
wires.
2. Check
UEL (921) and BRN (922) wires for
an open. If
engine does not crank, go to page 30-0 for
diagnosis of Starter and Charging Circuits.
C3. Reconnect the Starter Enable Relay and
connect a fused jumper from terminal A3
(DK GRN) wire of the PASSKEY Decoder
Module to ground. Ignition Switch to
START.
0 If engine cranks, replace the PASSKEY
Decoder Module.
If engine does not crank, check the DK
GRN (965) wire for
an open. If wire is OK,
replace the Starter Enable Relay.
6: STARTER ENABLE RELAY TEST
D: ECM ENABLE SIGNAL TEST
C2. Connect a fused jumper between terminals
Measure: VOLTAGE
At: STARTER ENABLE RELAY CONNECTOR
(Disconnected)
Condition:
0 Ignition Switch: START Measure:
VOLTAGE
At: PASSKEY DECODER MODULE
CONNECTOR (Connected)
Condition: 0 Ignition Switch: RUN
Measure
Between
&
Ground
&
Ground
Measure
Between I I For Diagnosis ( Voltage
1 I 5Volts I See 1 1
If voltages are correct, go to C2.
1. Check YEL (5) wire for an open. If wire is
good but voltage is not present, go to
8A-30 for diagnosis of Starter and Charg-
ing Circuits.
Correct
Voltage
Battery
Battery
I I
Ignition Switch: START
For Diagnosis
See 1
See 1
0 wait four minutes from last time Ignition
Switch was turned to OFF to
allow PAS-
SKEY Internal timer to reset.
I A2 IPPL)& ) 2 to3Volts I See2 i Ground
If voltages are correct, cranking Fuel
Enable signal is operating normally,
return to Symptom Table.
E (YEL) Vfire and A (DK GR wire 1 1. Check PPL (963) wire for an open. A of the Starter Enable Relay Connector. I I
(Continued in next column)
Ignition Switch to START.
If engine cranks proceed to
63.
Continued from previous column)
2. Replace PASSKEY Decoder Module.
Note: When the PASSKEY Decoder Module
is replaced, the key code
it is set for
may not match the code in the owner's
keys. If
it does not, then new keys
must be made. Use the procedure
under
Duplicgti~n of-Keys2
E: SECURITY INDICATOR OPEN TEST
CONNECTOR (Disconnected)
Condition:
KEY DUPLICATION PROCEDURE
Key Replacement (Spare Key Available)
The 535628 Interrogator or equivalent must
be used to det e
the proper electrical code
of the key.
1. Insert the customer's spare ignition key into
the Key Code Reader on the 535628 Inter-
rogator.
2. Press the On-Off rocker switch to the ON
position.

THEFT DETERRENT SYSTEM: PASSKEY
3. A number from 1 to 15 will appear in the
window designating the electrical code of
the key.
4. Cut a new key having the electrical code
ed from the 535628 Interrogator.
5. Start the engine using the new key to insure
that the key is correct both mechanically
and electrically.
Key Replacement (No Spare Key Available)
1. If the Ignition Key is lost and there is no
spare key, determine the mechanical code
from the code on the Ignition Key Lock
CyE
inder. The code may also be det
the dealer invoice for the car, or from the
Chewolet Zone Office.
2. Cut anew key to this mechanical code. Use a
blank PASSKEY test key which has no
resistance pellet. This key will be used to
operate the Ignition Switch for the remain-
ing steps.
3. Remove the hush panel under the steering
column and disconnect
C281 (two-cavity
connector leading into the steering column).
4. Insert the male half of the connector into the
female
pigtail connector from the 535628
Interrogator.
5. Set the Key Code Selector on the
Hnter-
rogator (535628 or equivalent) to "1 ".
6. Attempt to start engine using the key made
in step 2.
r If engine starts, the Key Code Selector is set
to the correct electrical code. Cut a new key
having this electrical code. The new key will
be customer's replacement key.
If engine does not start, turn Ignition
Switch to OFF, then turn the Key Code
Selector to the next higher position. Wait
four minutes and attempt to start the engine
using the new electrical code. Use the 4-min-
ute Timer on the 535628 Interrogator to
indicate the 4-minute interval. Start the
Timer by depressing the "Start" rocker
switch. The red indicator
will turn off at the
end of a four minute interval.
CIRCUIT OPERATION
Resistor senshg contacts are located in the
Ignition Key Lock Cylinder. These contact the
Key Resistor Pellet on the key when it is
inserted. When the lock is rotated, battery is
applied through the
CIH Fuse to the PASSKEY
Decoder Module. The Pellet resistance is then
colnpared against a fixed resistance in the Mod-
ule.
If the Key Pellet is the proper resistance, ter-
minal A3 is grounded, energizing the Starter
Enable Relay. At the
same time, a signal is
appfied at terminal A2 to enable the Electronic
Control Module
(ECM). When this signal is
received by the Electronic Control Module
(ECM), it allows fuel injector pulses to begin.
If the Key Resistor Pellet is the wrong
value,
the PASSKEY Decoder Module will shut down
tes. During this interval there
will be no output at terminals A3 or
A2.
If the Ignition Switch is turned on again dur-
ing this interval, the Timer will begin over
again and the PASSKEY Decoder Module
will
remain shut down for another 2 to 4 minutes.
The PASSKEY Decoder Module will continue
this process even if a key with the correct pellet
is used to turn the ignition back on. The Timer
is restarted by the ignition voltage at
t
A1 when Ignition Switch is turned to RUN.
Once the Timer has completed its
2 to 4 min-
ute cycle with the ignition off, the PASSKEY
Decoder Module and Timer are reset. A key
having the correct code can then be used to
start the engine.
The Security Indicator is controlled directly
by the PASSKEY Decoder Module. If there is a
PASSKEY Failure this indicator will be
grounded by the PASSKEY
Decoder Module
with the ignition in RUN,
BULB TEST or
START. When the Ignition Switch is first
placed in
RUN, BULB TEST or START the
Indicator lights for about 2 seconds as a bulb
check.

RADIO
SYSTEM CHECK TABLE
ACTION NORMAL RESULT FOR DlAGNOSlS OF OTHER RESULTS
Turn Ignition Switch to RUN or ACCU Time display appears Do
Test L, or if equipped with Remote Control do
Test A
Turn Radio on and tune
in a local station Power Antenna extends See
Power Antenna (Section 8A-151)
Center Balance and Fade Controls Program
is heard from all speakers without noise If
no sound comes from any Speaker, do Test G
or engine whine
If one or more Speakers do not operate, do Test D
on suspect
Speaker(s)
If excesssive noise is present, do Test H
Turn on Headlights or Park Lights and set
Radio digital display dims Do
test
N, or if equipped with Remote Control
Instrument Panel Lights to maximum
bright- Radio Panel Lamp khts Head, do test B
Lamps light (if equipped) Head,
do Test C
If all results are normal, the system is OK.

D: SPEAKER TEST (Continued from previous column)
At: RADIO OUTPUT FOR SUSPECT SPEAKER
Ignition Switch: RUN
o an authorized AC-Delco
E: REMOTE CONTROL SYSTEM TEST
(TABLE
1)
Measure: VOLTAGE
At: CONNECTOR C210 (Connected)
Conditions: Ignition Switch: RUN
. Headlights: ON
I r Instrument Panel at maximum I brightness
I Measure I I For Diagnosis ( Between
I & I Battery I See 1 1 Ground I I I I
(Continued in next column)
D (YEL) & B
(BLKILT Battery See 2
BLU)
(GRY) & Battery
Ground See 3
If all voltages correct, go to Table
2.
1. Check YEL (43) wire.
2. Check BLKILT BLU (151) wire for an
open to ground (see schematic).
3. Check GRY
(8) wire.
E: REMOTE CONTROL SYSTEM TEST
(TABLE 2)
At: CONNECTOR 6210 (Connected)
Condition:
Measure
Between
I tz I For Diagnosis
1 I - I
A (ORN) & Between 4.5
Ground and 5.5 volts See 1
Press
the Preset, Mute, and RCL buttons
on the Remote Control
Head simul-
taneously
r Turn the steering wheel slowly while mea-
Between 2.0
at
all positions
If
all voltages are correct, check ORN
(917) wire to the Radio. Send Radio to an
authorized AC-Delco repair station if wir-
ing and connections are OK. Refer to Sec-
tion
9A for removal and replacement
~rocedures. ---- - -
(Continued in next column) (Continued from
previous
column)
Refer to Section 3B5 for replacement pro-
cedures.
2. DoTest F.
F: OPTlCAL SLlPRlNG TEST (TABLE 1 )
e Remove the Remote Control Head. Refer to
Section 3B5 for removal procedures.
r Install tool 5-353630 between the Control
Head and connector
C1 (see section 3B5).
Make the following measurements.
At: TOOL 5-35630 (Connected)
Engine running
0 Light Switch: MEAD or PARK
0 lnstrument Panel Lights at maximum
@ If all voltages are correct, go to Table 2.
(Continued on next page)

RADIO
(Continued from previous page)
1. Remove the Cancel Cam. Inspect the Slip
Rings on the Cancel Cam and the spring
loaded contacts on the Turn Signal
Switch. Replace as necessary. Incorrect
or missinglubricant on the Cam can cause
premature failure. Take care to keep lubri-
cant or any foreign material away from
the
LED'S and receptors as it will hinder
or prevent proper operation. The correct
lubricant is part no.
26002312.
F: OPTICAL SLlPRlNG TEST (TABLE 2)
Measure: VOLTAGE
At: TOOL J-35630 (Connected)
Conditions:
@ Engine running
0 Press the Preset, Mute and RCL buttons
or the Seek, Scan, and
AMIFM buttons
on the Remote Control Head
sirnultaneoulsy
0 Turn the steering wheel slowly while
measuring
Measure
Correct I For Diagnosis I
I I Between 3.0 1 I Terminal C & and 4.5 volts
1 Ground 1 at all wheel
I 1 positions I I
I . If the voltage is correct, go to Table 3. (
1. Replace the Remote Control Head. Refer
to Section
3B5 for replacement pro-
cedures.
F: OPTICAL SLlPRllUG TEST (TABLE 3) H: NOlSE DIAGNOSIS
Remove the Cancel Cam. Refer to Section Unplug
the Antenna at the back of the Radio.
3B5 for removal procedures.
If noise disappears, it was being picked up
0 Make the following measurements.
by the Antenna. Consult the Delco Sound
Service Guide for Antenna noise diagnosis.
If the noise persists, it is coming in the Radio
wiring. Refer to the following chart for a
possible cause and corrective action.
At: CONNECTOR 6210 (Connected)
@ Ignition Switch: RUN
Shield the Turn Signal Switch Light
Receptors from outside light with a dark
1. Replace the Turn Signal Switch. Refer to
6: ANTENNA TEST
Check connectors Radio and Antenna ends of
Antenna Coaxial Cable. Connect a known good
test Antenna to the Radio. The test Antenna
must be designed for use
with ARC Radios, as
ARC Radios use a different size Antenna con-
nector than conventional Radios.
@ If Radio plays, replace the Antenna.
If Radio still does not operate, send Radio to
an authorized AC-Delco repair station.
Refer to section 9A for removal and replace-
ment procedures.

RADIO I
(Continued from previous page) from back of Radio
If noise persists with replacement antenna, the
problem must be repaired at the source of noise
(generator, ignition system, accessory, etc.). See
Delco Manual for noise "Sniffing" procedures.
Ignition Noise
Trv the following. fixes in the piven order: 8. Install a braided ground strap on the hood. Replace
defective antenna with a good antenna.
If noise disappears repair or replace the defective
antenna. Check antenna ground, Coaxial Cable
Braid, and ground at connectors.
unplugged
- -
1. Check
for loose or defective spark plug wire.
2. Check for defective spark plug.
3. Move all wiring away from Ignition System
and spark plug wires. Antenna
noise
4. Reroute spark plug wires laying against
anything that could possibly transmit noise
to the Radio (car
g or sensor leads that
travel into the passenger compartment).
5. Inspect Ignition system for the following
and replace if necessary:
r Distributor cap carbon ball eroded away,
cracked or loose cap.
A rotor with burned black spot on wiper or
pits in wiper surface.
r A defective coil.
r An oily film on some of the lead terminals or
inside the cap.
Defective
WE1 module; can cause ignition
noise on
FM only.
6. Replace distributor cap and rotor.
9. Check Heater Core ground; clean or install a
braided ground strap if necessary.
10. Check air conditioner accumulator ground;
clean or install a braided ground strap if
necessarv.
TO STEERING
BRAIDED
GROUN GO LUMN
Figure 1 - Gut the BLACK (ground) wire from
the black plug
at the back of the Radio and run
7. Check the ground from engine to firewall, a braided ground strap from the ease of the
install a braided ground strap if necessary. Radio to good, unpainted body ground.
(TRY GROUNDED AND UNGROUNDED)
POWER LlNE TO RADIO
(IGNITION OR MEMORY)
Figure 2 - install a 1224205 filter package.