Put the multimeter leads on terminals "A" and "B".
The resistance should be between 30 and 34 ohms If
the resistance is not correct, replace the start relay.
If the resistance is correct, disconnect terminals "4" "7",
"6" and "9".
Put the leads of the 8S-4627 Test Light between
terminals "4" and "7". The test light should not turn on.
Put the leads of the test light on terminals "6" and "9".
The test light should not turn on.
If the test light turns on, the start relay must be replaced.
Troubleshooting for other tests of the starting system.
The condition of the charge in the battery at each regular
inspection will indicate if the charging system operates
correctly. A problem exists when the battery is constantly in a
condition of low charge. A problem also exists if more than
one ounce of water must be added to a cell in the battery
during the following periods:
Each 100 hours of operation
Testing the charging system is preferable when the following
The alternator is mounted on the engine.
The voltage regulator is mounted on the engine.
The wiring and electrical components which are used in
the test are a permanent par of the electrical system.
Bench testing can be done on the alternator and the voltage
regulator. This testing will determine if the individual
component is defective.
When a component is replaced or repaired, the charging
system should be tested. This test will verify that the charging
system is operating correctly.
Refer to Specifications, "Alternator and Regulator for additional
Before the charging system is tested on the engine, the
charging system and the battery must be inspected. Use the
following inspection procedures:
The battery must be charged to at least 75% of rated
power output. The specific gravity of the solution in the
battery should be 1.225. The battery should be held
firmly in place. The battery holder must not put too
much stress on the battery.
The cables between the battery, the starter, and the
ground of the engine must be the correct size. Wires
and cables must be free of corrosion. The wires and the
cables should have cable support clamps in order to
prevent stress on the battery connections.
The leads, the junctions, the switches, and the panel
instruments which relate to the charging system must
The alternator and the drive components for the
alternator must operate correctly.
Put the positive lead "+" of the multimeter on the "Bat"
terminal of the alternator. Put the negative " lead on the
ground terminal or on the frame of the alternator. Put
the ammeter around the positive output wire of the
Turn off all electrical accessories. Turn off the fuel to
the engine. Crank the engine for 30 seconds. Wait for
two minutes in order to cool the starting motor. If the
electrical system appears to operate correctly, crank the
engine again for 30 seconds.
Cranking the engine for 30 seconds partially
discharges the batteries in order to do a charging
test. If the battery has a low charge, do not
perform this step. Jump start the engine or
charge the battery before starting the engine.
Start the engine and run at full throttle.
Check the output current of the alternator. The initial
charging current should be equal to the minimum full
load current or the initial charging current should be
greater than the minimum full load current. Refer to
Specifications, "Alternator and Regulator for the correct
minimum full load current at different rpm.