Electronic Engine Control self test for Ford vehicles with EEC IV
WARNING!
FOLLOW STANDARD SAFETY PRACTICES WHEN WORKING ON A VEHICLE INCLUDING BUT NOT LIMITED TO:
Transmission in Park or Neutral and the driven wheels off the ground or chocked when cranking/running
the engine.
Check fan blade for cracks and do not stand next to the fan when engine is running.
Use caution when working on fuel systems, which can remain pressurized for a long period after the key
is turned off.
No smoking around fuel.
Watch for electric fan which can come on at any time.
Watch out for hot and/or moving parts.
When working on a no-start vehicle, use a neon spark tester to check for spark and ground the coil wire
to prevent accidental starting if spark should occur while testing.
Watch out for high voltage secondary circuits.
If you are not sure of the safety of any operation DO NOT DO IT. ASK SOMEONE!
2 Digit EEC codes
3 Digit EEC codes
CODE TYPES AND FORMATS
CODE FORMATS
Codes are output as a series of pulses. The following charts show the (approximate) timing of the various code pulses.
NOTE: Two digit codes are shown. Three digit codes have similar timing. It just takes a little practice to distinguish between two and three
digit types.

TESTS
NOTE: Vehicle should be fully warmed for all tests.
HOOKUP
See figure below. EEC IV vehicles have two connectors for self testing the system. They are located on the firewall
or the left or right front fender. The large connector contains the self test output (STO) and ground (SIG RTN). The small pigtail is
the self test input (STI).
© Copyright 1997-2005 Dali Design
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