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Sensor and Actuator Diagnostic Procedures






WARNING: RED-STRIPED WIRES CARRY 115V DC. SEVERE ELECTRICAL SHOCK MAY BE RECEIVED. DO NOT PIERCE.


CAUTION: Do not pierce engine electrical wires or damage to the harness may occur.

Operational Signal Checks
These checks are made with the Rotunda 104-pin Breakout Box 014-00950 installed and normally measure a signal voltage or frequency. They are useful for determining an in-range type concern, or an intermittent connection.

In the case of an intermittent concern, monitoring a suspected circuit and recreating the environmental or physical conditions that caused the complaint will help verify if a problem is in a particular circuit.

It is critical when measuring the signal level of a circuit to understand the function and whether it is an analog voltage, digital frequency, sine wave or digital communication signal. A standard Digital Volt-Ohmmeter (DVOM) has certain limitations in measuring any circuit that has a frequency.