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Home >> Lincoln >> 1994 >> Mark VIII V8-4.6L DOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Pinpoint Tests >> XB - Variable Control Relay Module (VCRM) >> XB166 - Check HFP Circuit For Short to Power
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XB166 - Check HFP Circuit For Short to Power



- Key "OFF".

- High Speed Fuel Pump (HFP) relay disconnected.

- Disconnect Variable Control Relay Module (VCRM).

- Key "ON".

- Measure voltage between the HFP circuit at the HFP relay vehicle harness connector and the battery negative post.

- Key "OFF".

- Was voltage less than 1.0 volt?

Yes -- Go to XB167. XB167 - Check HFP Circuit For Short to Ground

No -- Service High Speed Fuel Pump (HFP) circuit short to power. Reconnect all components. Re-evaluate symptom.

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