Equus 3145 - Digital Ford Code Reader (1981 - 1995) User Manual
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About Diagnostic Systems
FORD COMPUTER SYSTEM OVERVIEW
15
Chapter 2
IMPORTANT:
When the computer is in Self Test mode (is
testing the sensors or actuators for proper operation), it relies
on voltage signals that it sends to and/or receives from the
sensors or actuators to determine whether or not these
components are operating properly. The sensors and actuators
are all connected to the computer by wires. If any defects are
present in any part of the circuit that connects these devices to
the computer (such as defective connectors or wires, faulty
grounds, improper voltage, shorts etc.), the voltage signal that
the computer receives from these devices will be affected. The
computer has no way of determining if the improper voltage
signal is being caused by a defect in the circuit or by the sensors
or actuators themselves. Keep this in mind when servicing
Fault Codes, and do not replace any devices (sensors or
actuators) before checking the complete circuit (or circuits) that
are part of the device from which the code was generated.
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