Hall Sender (Cabriolet, Golf & Jetta)

Remove coil secondary and attach to ground. Disconnect hall sender wire harness connector at distributor. Using a LED Test Light (US 1115), check for voltage between outer terminals of connector. See Fig 1 . With ignition on, light should be on. If not, check wiring for short or open circuit. If not, replace ignition control unit.
If light came on in step 1), pull back hall sender boot to expose contact terminals. Apply LED Test Light (US 1115) probe to center contact and battery positive terminal. See Fig 1 . Observe test light while cranking engine. If test light blinks, hall sender is okay. If not, replace hall sender.

Fig 1: Typical Hall Sender Test Procedure

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