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TM 10-3930-669-34
2-8. TROUBLESHOOTING INSTRUCTIONS (CONT).
(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.
(c)
Disconnect harness connector.
(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.
2-9. TROUBLESHOOTING SYMPTOMS.
The Troubleshooting Symptom Index (Table 2-3) lists the most common failure symptoms found during operation of the
forklift. Find the symptom that is closest to the symptom your forklift has and refer to that paragraph for the
troubleshooting procedure.
Table 2-2. Troubleshooting Symptom Index
Para
Description
Page
2-14
Engine System Troubleshooting.....................................................................................................2-10
2-15
Drive Axle Troubleshooting ............................................................................................................2-70
2-8
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