Pontiac Fiero 1988 Service Manual page 614

DRIVEABILITY AND EMISSIONS - FUEL INJECTION (PORT) 6E3-A-31
CODE 15
COOLANT TEMPERATURE SENSOR CIRCUIT
(LOWTEMPERATURE INDICATED)
2.8L "P" SERIES (PORT)
©
DOES " S C A N " DISPLAY COOLANT -30°C OR COLDER?
YES
©
• DISCONNECT SENSOR
* JUMPER HARNESS TERMINALS TOGETHER
" S C A N " SHOULD DISPLAY 130°C OR MORE.
DOES IT?
YES
FAULTY CONNECTION OR SENSOR.
©
NO
CODE 15 IS INTERMITTENT. IF NO
ADDITIONAL CODES WERE STORED, REFER
TO "DIAGNOSTIC AIDS" ON FACING PAGE.
NO
JUMPER CKT 410 TO GROUND.
" S C A N " SHOULD DISPLAY OVER 130°C.
DOES IT?
DIAGNOSTIC AID
COOLANT SENSOR
T E M P - R A T U R E TO RESISTANCE VALUES
(APPROXIMATE)
°F
°C OHMS
210 100 185
160
70 450
100 38 1,800
70 20 3,400
40 4
7,500
20 -7 13,500
0 -18 25,000
-40 -40 100,700
YES
OPEN SENSOR GROUND
CIRCUIT, FAULTY
CONNECTION OR
FAULTY ECM.
NO
X
OPEN CKT 410, FAULTY
CONNECTION AT E C M , OR
FAULTY ECM.
CLEAR CODES AND CONFIRM " C L O S E D L O O P " OPERATION AND NO "SERVICE ENGINE S O O N " LIGHT.
2-11-87
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