Sensor and Actuator Diagnostic Procedures

OPERATIONAL SIGNAL CHECKS
These checks are made with the breakout box 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 multimeter has certain limitations in measuring any circuit that has a frequency.

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

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