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Hall Control Unit Test

NOTE: Perform this test on GLI and GTI models only. Use Test Lamp (US 1115 ) only. Use of "standard" test lamps can damage ignition system components.
  1. Disconnect Hall control unit (in glove box). Set Digital Multimeter (US 1119 ) on 20 volt scale. Connect multimeter between terminal 2 (negative) and 4 (positive) of control unit connector. Turn ignition on. Voltmeter should indicate battery voltage. If not, repair circuit in wiring.
  2. Connect Test Lamp (US 1115 ) to terminal 4 and 6 of control unit connector. See Figure. Crank engine and check signal from sending unit. If test lamp LED flickers, sending unit is okay. If not, turn ignition off and reconnect Hall control unit.
  3. Remove connector from sending unit at distributor. Connect multimeter between negative terminal 1 and positive terminal 15 on ignition coil. Turn ignition on.
  4. Initial meter reading should be 2 volts minimum, then voltage must drop to zero after 1-2 seconds. If reading is incorrect, replace Hall control unit.
  5. Check ignition coil and see if any sealing compound has leaked out. Replace coil if necessary. Briefly tap connector center terminal against engine ground.
  6. Displayed voltage must increase a minimum of 2 volts for a short time. If reading is incorrect, replace Hall control unit. Turn ignition off and reconnect sending unit.
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