Service Manual

Starter Magnetic Switch ISB, ISBe and QSB (Common Rail [...]
Page 13-20 Section 13 - Electrical Equipment - Group 13
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Resistance Check
WARNING
Be sure the starter motor switch is in the OFF
position to reduce the possibility of electrical shock
and personal injury.
Remove the cable connecting the magnetic switch to the
starter motor solenoid from the magnetic switch terminal.
Connect the leads of the digital multimeter, Part Number
3377161, or equivalent, to the two large switch terminals.
Set the digital multimeter, Part Number 3377161, to
measure resistance (ohms).
Connect the leads to the two large switch terminals.
With the keyswitch in the OFF position, the multimeter
must indicate resistance greater than 100k ohms.
Turn the keyswitch to the START position.
The multimeter must indicate less than 10 ohms. If not
within specifications, replace the starter magnetic switch
according to the manufacturer's instructions.
Voltage Check
If the multimeter indicates resistance greater than 100k
ohms with the keyswitch in the START position:
• Turn the keyswitch to the OFF position.
• Set the multimeter scale to read DC voltage.
• Connect one multimeter lead to the magnetic switch
terminal marked S and the other lead to ground.
• Turn the keyswitch to the START position.
• If the multimeter indicates no voltage, the magnetic
switch is not the cause of the complaint. If the starter
magnetic switch is not within specification, replace the
switch according to the manufacturer's instructions.