GENERAL TROUBLESHOOTING INSTRUCTIONS - continued

TM 10-3930-673-20-1

(d) Connect the positive (+) multimeter lead to the circuit being tested. Connect the negative () multimeter lead

to a known good ground.

(e) Set main power switch to the ON position and operate any other controls necessary to energize the circuit

being tested.

(f) Read the voltage value displayed on the multimeter.

(g) Set the main power switch to the OFF position. Return other controls to their "at rest" positions.

(h) Disconnect multimeter leads from circuit.

(i) Turn off multimeter.

(3) General Relay Troubleshooting Procedure. The following general relay troubleshooting procedure applies to most

relays that are pushed into a receptacle and do not require any attaching hardware.

(a) Pull relay out of receptacle just enough for the relay terminals to make contact with receptacle terminals.

Leave about 1/4 to 3/8 in. (6.35 to 9.53 mm) space between the relay and the receptacle to insert a multimeter lead and make

contact with the terminal listed in the troubleshooting test.

(b) Perform necessary test.

(4) General Wiring Harness Short Test. The following procedure applies to any wiring harness suspected of being

shorted. Refer to electrical schematics during this procedure.

(a) Connect positive (+) multimeter lead to multimeter VOLT-OHM connector. Connect

negative () multimeter lead to multimeter COM connector. When the multimeter leads are separated or are measuring a

circuit with no continuity, the multimeter will indicate "OL" (Over Limit) on its display. When multimeter leads are connected

together, multimeter should display "0," indicating a continuous circuit with no (zero) resistance. Wires in a harness that are

not purposely joined or connected at a component should not have continuity (multimeter indicates "OL").

(b) Set multimeter function/range switch to the highest OHM range.

(d) Connect positive (+) multimeter lead to harness connector terminal of suspected wire.

(e) Connect negative () multimeter lead to each of the remaining harness connector terminals. If multimeter does

not display "OL," and is displaying a resistance value of zero or higher, this indicates a continuous circuit. Refer to the

electrical schematic before repairing wires or replacing wiring harness to determine that the wires making a continuous circuit

are not purposely joined or are not connected intentionally at a component.

(f) Disconnect multimeter leads from connector.

(g) Turn off multimeter.

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