Component Tests; Check/Clean Wires And Connectors; Check/Clean Ground Cable - Simplicity Legacy Series Service & Repair Manual

7 Electrical System Service

Component Tests

WARNING
Before beginning any test,
ALWAYS:
• Disconnect the spark plug wire.
• Block the wheels.
IN MOST CASES:
• Engage the parking brake.
• Turn the PTO switch OFF.
• Turn the ignition switch OFF.
• Place the ground speed control lever in
NEUTRAL (Peerless models only).
If a test procedure requires a configuration other
than the one listed above, instructions will be pro-
vided in that specific procedure.
Always reset the tractor to the configuration listed
above unless told otherwise.
ELECTRICAL SYSTEM TESTING
The following tests should be used in conjunction with
this sections troubleshooting flow charts to efficiently
troubleshoot common electrical problems; however, if a
specific component is suspect, these tests can be used
independently of the flow chart and of each other.
Common Component Test
FUSES (EARLY DIESEL MODELS ONLY)
The electrical circuits for the early model tractors are pro-
tected by a fuse instead of a circuit breaker and fusible
links. The fuse block is located on the firewall.
A blown fuse is easily identified by using an ohm meter
to check for continuity.
Be sure to replace the blown fuse with the correct type.
If the replacement fuse immediately fails, don't replace it
again until the cause of the problem is isolated and cor-
rected. In most cases, the cause will be a short circuit in
the wiring caused by a broken or deteriorated wire.
CIRCUIT BREAKERS (LATER MODELS)
All circuit breakers are located on the firewall. The circuit
breaker resets itself automatically. If the circuit doesn't
come back on, check it immediately.
GLOW PLUG RELAY (DIESEL TRACTOR MODELS)
The electrical system uses a relay to transmit the electri-
cal power to the component. If the relay is defective, the
component will not operate properly. The relay is located
on the firewall.
Check for
Corrosion
Figure 32. Typical Wire Harness
A. Check/Clean Wires and Connectors
1. Check all wires for cracked or worn insulation.
2. Check all connectors, terminals, and receptacles for
loose wires or corrosion (Figure 32). Refer to the
exploded view diagrams for wire harness locations.
Figure 33. Testing Cable Continuity
B. Check/Clean Ground Cable
1. Disconnect and secure the negative battery cable
(see Section 6, COMMON SERVICE PROCE-
DURES).
2. Disconnect the other end of the negative battery
cable (ground cable) from the engine.
3. Clean the battery and cable terminals with a wire
brush until the metal is shiny.
4. Using a VOM set to Ohm, test the continuity of the
cable (Figure 33). The VOM should register no more
than 2-3 ohm.
5. Clean the negative battery post and engine ground
with a wire brush until the metal is shiny.
6. Reattach the negative cable to the engine block and
then the negative battery terminal.
7 - 34
Check for
Loose Wires
Inspect
Insulation