Pontiac Fiero 1988 Service Manual page 1087

INSTRUMENT PANEL: INDICATORS C L U S T E R
(Continued from previous page)
• If the Coolant Temperature Gage reads cor-
rectly, the wiring and Gage are good.
Replace the Coolant Temperature Sender/
Switch.
• If the Gage is not correct, check the Gage
connection and the DK GRN/YEL (135) wire
for high resistance. If OK replace the
Coolant Temperature Gage (see Section 8C).
J : C O O L A N T T E M P E R A T U R E
I N D I C A T O R SHORT T E S T
Disconnect the Coolant Temperature Sender/
Switch and put the Ignition Switch in RUN.
• If the Indicator stays on, check the DK GRN
(35) wire and Printed Circuit for a short to
ground.
• If the Indicator goes out, replace the Coolant
Temperature Sender/Switch.
K: C O O L A N T T E M P E R A T U R E
I N D I C A T O R O P E N T E S T
Connect: A FUSED JUMPER
At: COOLANT TEMPERATURE SENDER/
SWITCH CONNECTOR (Disconnected)
Condition:
• Ignition Switch: RUN
Jumper
Between
Correct Result For Diagnosis
B (DK GRN)
& Ground
Coolant
Temperature
Indicator
comes on
Seel
(Continued in next column)
Continued from previous column)
• If the result is correct, replace Coolant
Temperature Sender/Switch.
1. Check DK GRN (35) wire and Instrument
Cluster Printed Circuit for an open.
L: OIL P R E S S U R E G A G E S H O R T T E S T
Disconnect: CONNECTOR
A t : OIL PRESSURE SENDER
Condition:
• Ignition Switch: RUN
Action Correct Result
Fo~ Diagnosis
Disconnect Oil
Pressure
Sender
Connector
Oil Pressure
Gage shows
high pressure
Seel
• If the result is correct, replace the Oil
Pressure Sender.
1. Check TAN (31) wire (see schematic) for
for a short to ground. Replace the Oil
Pressure Gage, if the wire is OK (see Sec-
tion 8C).
M: OIL PRESSURE GAGE OPEN TEST
Connect: FUSED JUMPER
At: OIL PRESSURE SENDER CONNECTOR
(Disconnected)
Condition:
• Ignition Switch: RUN
Jumper
Between
Correct Result For Diagnosis
A (TAN) &
Ground
Oil Pressure
Gage shows
low pressure
Seel
(Continued in next column)
(Continued from previous column)
• If the result is correct, replace the Oil
Pressure Sender.
1. Check TAN (31) wire and Instrument
Cluster Printed Circuit for an open. If
wire and Printed Circuit are OK, replace
the Oil Pressure Gage (see Section 8C). .
N: OIL P R E S S U R E G A G E A C C U R A C Y
T E S T
Disconnect the Oil Pressure Sender. Connect
one red clip lead of the J-33431 tester to the
harness connector, TAN (31) wire, and connect
the other red clip lead to ground. Set the
resistance dials of the sender to 0 ohms and
then to 90 ohms. The Oil Pressure Gage should
read low pressure and then high pressure.
• If the Oil Pressure Gage reads correctly,
replace the Oil Pressure Sender.
• If the Oil Pressure Gage does not read cor-
rectly, check the TAN (31) wire, the Gage
connections, and Printed Circuit. If they are
good, replace the Oil Pressure Gage (see Sec-
tion 8C).
O: V O L T M E T E R T E S T
With the Ignition Switch in RUN, connect a
voltmeter between the positive and negative
terminals of the Battery.
• If the voltage reading on the test voltmeter
is the same as the car's Voltmeter, the car's
Voltmeter is OK.