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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) >> XB160 - Lack of Power/Hard Start: Verify HFP Operation
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XB160 - Lack of Power/Hard Start: Verify HFP Operation



- Key "OFF".

- Disconnect High Speed Fuel Pump (HFP) relay (located in Power Distribution Box).

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

- Key "ON".

High Fuel Pump Relay Connector:






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

- Key "OFF".

- Were both voltages greater than 10.5 volts?

Yes -- Go to XB161. XB161 - Check Power to Pump Circuit Continuity

No -- Service open in B(+) or IGN Start/Run circuit (verify condition of related fuses). Reconnect all components. Re-evaluate symptom.
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