Electrical System Quick Checks; Battery Test; Charging System Test; Voltage Drop Testing - Toro Reelmaster 4500–D Service Manual

Electrical System Quick Checks

Battery Test

Use a volt–ohm multi–meter to measure the voltage be-
tween the battery terminals.
Set the multi–meter to the DC Volts setting. The battery
should be at a temperature of 60 to 100 F. The ignition
key should be off and all accessories turned off. Connect
the positive (+) Volt meter lead to the positive battery
post and the negative (–) Voltmeter lead the the nega-
tive battery post.
NOTE: This test provides a relative condition of the bat-
tery. Load testing of the battery will provide additional
and more accurate information.

Charging System Test

This is a simple test used to determine if a Charging sys-
tem is functioning. It will tell you if the charging system
has an output, but not how much (amps) or what it is ca -
pable of.
Tool required: Digital Multimeter – DC volts setting.
Test instructions: Connect the positive (+) DVOM test
Lead on the positive Battery Post, and negative (–) Lead
on the negative Battery Post. Leave test leads con-

Voltage Drop Testing

This is a simple test that should be used to locate excess
resistance in an electrical circuit.
Tool required: Digital Multimeter – DC volts setting.
Test instructions: Connect the positive (+) DVOM test
lead to the power side (or most positive) of the compo-
nent, circuit or connection. Connect the negative (–)
DVOM test lead to the ground side (or least positive) of
the component, circuit or connection. Turn on the circuit
to be tested and read the voltage. Remember – when
Reelmaster 4500–D
Voltage Measured
12.6 V (or higher)
12.4 V
12.2 V
12.0 V
NOTE: Regulated voltage will increase to approximately
13.5 Volts when the engine is running.
nected and start engine and run at 2000 RPM minimum.
Test results should be:
At least 1 volt over Open Circuit test results.
Example: Open Circuit Test results
Charging System Test results
Difference
performing voltage drop tests the circuit must be com-
plete and activated to locate the resistance!
Voltage Drop Specifications (Maximums)
High Amperage
Circuits ( 20 A.)
.4 volt feed side
.4 volt ground side
Page 5 – 19
Battery Charge
Fully charged (100%)
75% charged
50% charged
25% charged
= 12.5v
= 13.5v
= +1.0 v
Low Amperage
Circuits ( 20 A.)
.2 volt feed side
.2 volt ground side
Electrical System