Ford Corsar Repair Manual page 195

TROUBLE DIAGNOSES
SELF DIAGNOSIS SYSTEM CHECK
Ignition on engine stopped.
Diagnostic bridge removed.
Note ECM light.
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Note and record any malfunction codes.
Code 12 isnot a malfunction code.
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If flashing code 55.
Check for
Perform Diagnostic Procedure
2 1
t o check Vehicle Speed Sensor.
Perform Diagnostic Procedure
17
t o check ParkINeutral switch
(A/T
models only)
Note and record any malfunction codes. Code
12
is
not
a malfunction code.
Flashing Light No Light
Does not flash
any code.
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Go to Diagnostic
Procedure 1
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No Malfunction Codes Malfunction Codes
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Steady Light
see code 55 chart first.
Flashes code 12
intermittent
Otherwise. Check diagnostic
short to earth
or any
circuit AN114 for a short to earth.
onAN114
malfunction code.
If not earthed. Check for a
short to 12 volts on AN 1 14.
If AN114 is ok, it is a faulty ECM.
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If flashing code
55
see that chart first. Otherwise.
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See applicable chart. If more than one code
Diagnostic circuit check ok
is stored. Start with the lowest code. If engine
if engine cranks but will not run, go to Diagnostic Procedure 2.
cranks but , , , , i l l not run, go to ~ i ~ ~ ~ procedure 2.
Go to Diagnostic
Procedure 1.
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Enter field service mode by running engine with Diagnostic Bridge connected.
Note ignition timing will stay in the "Set Timing" mode with rpm below 2000.
With engine at normal operating temp. Run at 1600-1800 rpm for two minutes and note ECM liqht.
Light flashes at a
1 per sec. confirming
rate of 2.5 per sec
"Closed Loop" operation. indicating "Open
Loop" operation.
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Fuel system operating
normally.
Connect diagnostic
bridge and note
ECM light.
Light is off all
or most of the
time, indicating
a lean exhaust.
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Light is on all
or most of the
time, indicating
a rich exhaust.
Flashing code 12
or other codes.
Vehicle may be driven in the field service mode and evaluated at any steady speed. This can be helpful
in diagnosing drive ability problems that involve the fuel control system being rich or lean too long.
Erratic or at
times intermittent.
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