Service Manual

Groundsmaster 4300--D Page 5 -- 17 Electrical System
Electrical System Quick Checks
Battery Test (Open Circuit Test)
Use a digital multimeter to measure the battery voltage.
Set the multimeter to the DC volts setting. The battery
should be at a temperature of 60
o
to 100
o
F(16
o
to
38
o
C). The ignition switch should be in the OFF position
and all accessories turned off. Connect the positive (+)
multimeter lead to the positive battery post and the neg-
ative (--) multimeter lead to the negative battery post.
Record the battery voltage.
NOTE: This test providesa relative condition of the bat-
tery. Load testing of the battery will provide additional
and more accurate information (see Battery Service in
the Service and Repairs section).
Voltage Measured
Battery Charge Level
12.68 volts Fully charged (100%)
12.45 volts 75% charged
12.24 volts 50% charged
12.06 volts 25% charged
11.89 volts 0% charged
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 its capacity.
Use a digital multimeter set to DC volts. Connect the
positive (+) multimeter lead to the positive battery post
and the negative (--) multimeter lead to the negative bat-
tery post. Keep the test leads connected to the battery
posts and record the battery voltage.
NOTE: Upon starting the engine, the battery voltage
will drop and then should increase once the engine is
running.
NOTE: Depending upon the condition of the battery
charge and battery temperature, the battery voltage will
increase at different rates as the battery charges.
Start the engine and run at high idle (3200 RPM). Allow
the battery to charge for at least three (3) minutes. Re-
cord the battery voltage.
After running the engine for at least three (3) minutes,
battery voltage should be at least 0.50 volt higher than
initial battery voltage.
An example of a charging system that is functioning:
At least 0.50 volt over initial battery voltage.
Initial Battery Voltage = 12.30 v
Battery Voltage after 3 Minute Charge = 12.85 v
Difference = +0.55 v
Glow Plug System Test
This is a fast, simple test that can help to determine the
integrity and operation of your Groundsmaster glow
plug system. The test should be run anytime hard start-
ing (cold engine) is encountered on a diesel engine
equipped with a glow plug system.
Use a digital multimeter and/or inductive Ammeter (AC/
DCCurrentTransducer).Properly connect theammeter
to the digital multimeter (refer to manufacturers’ instruc-
tions) and set the multimeter to the correct scale. With
the ignition switch in the OFF position, place the
ammeter pickup around the main glow plug power sup-
ply wire and read the meter prior to activating the glow
plug system. Adjust the meter to read zero (if applica-
ble). Activate the glow plug system by turning the igni-
tion switch to RUN and record the multimeter results.
The Groundsmaster 4300--D glow plug system should
have a reading of approximately 36 amps total (9 amps
per glow plug). If low current reading is observed, one
(or more) glow plugs is faulty.
Electrical
System