Equus 3145 - Digital Ford Code Reader (1981 - 1995) - Manual (Page 30)

Retrieving Codes
KOEO TEST PROCEDURES (EEC-IV SYSTEMS)
27 Chapter 4
WARNING: On some vehicles equipped with an
Electric Cooling Fan, the computer activates the
cooling fan to check its operation. To avoid
injury, keep hands or any part of your body a
safe distance from engine during the test.
8. After 6 to 10 seconds (it may take longer on some vehicles)
the computer will start sending the KOEO Self Test
results to the Code Reader in the form of numerical codes.
NOTE: Most Ford EEC-IV vehicle computers up to 1991
use a two-digit code system. From 1991 to 1995 most use a
three-digit code system.
■ A square icon (on the right-
hand side of the screen)
displays and flashes each
time the Code Reader
receives a code. The code is
then shown on the Code
Reader's display.
■ A small "O" is shown in the upper right-hand corner
of the display to indicate that the code being received
is a KOEO Self Test fault code.
NOTE: Each code is repeated two times.
9. If no problems are found during
the KOEO Self Test, the
computer sends a “pass code”
(code 11 or 111) to the Code
Reader.
■ Code 11 or 111 indicates that
all the relays and actuators
(and their related circuits)
that were tested are OK, and
no faults were found.
■ If the Code Reader fails to display codes, consult the
troubleshooting guide on pages 75 and 76.
10. Approximately six to nine seconds
after the Code Reader receives
the last KOEO Self Test fault
code(s), a “separation code” (code
10) is sent to the Code Reader.
O
O
O
4