Troubleshooting Starter With Digital Multimeter - Volvo VN 2002 Service Manual

Group 33 Starting and Charging
Troubleshooting Starter with Digi-
tal Multimeter
The starter motor/solenoid is supplied power and ground
through cables connected directly to the batteries. The
starter solenoid is engaged when a 12 volt signal is de-
livered to the "SW" terminal via the starter relay(s).
When the starter solenoid engages, a connection is
made internally in the solenoid that connects the battery
and motor terminals and the starter cranks the engine.
1 Check for 12.4V at the battery cable terminals that
are connected to the starter motor. If 12.4 V is not
present or if a weak battery(s) is suspected, see:
"Battery Troubleshooting" page 15 for battery testing
information.
2 Confirm that the cables between batteries are clean
tight and in proper working order.
3 Remove the engine ECU fuses located in the battery
box to prevent the engine from running during tests.
Use a digital multimeter J-39200 or equivalent tool to per-
form the test in the following table. The measuring points
referenced in the table as H, I and G. correspond to
measuring points that are found in the following illustra-
tions. For a view of the schematic see "Troubleshooting
Simplified Schematic, Delco 42MT Starting System"
page 19 or "Troubleshooting Simplified Schematic, Volvo
Gear-reduction Starting System" page 20.
Troubleshooting
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