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Hall Effect Switch Test

NOTE: Hall Effect switches cannot be checked with an ohmmeter.
  1. Disconnect 3-wire connector at Hall Effect switch. Connect a 12-volt battery and voltmeter to switch terminals. See Fig 1. Carefully note polarity markings.
    Fig 1: Testing Hall Effect Switch
    G12873Courtesy of GENERAL MOTORS CORP.
  2. Insert knife blade between magnet and Hall Effect switch. See Fig 1. Voltmeter should read within .5 volts of battery voltage. With knife blade removed voltmeter should read 0-.5 volts. If voltage readings are not as specified, replace Hall Effect switch.