What does P1651 mean on a Ford?

P1651. Power Steering Pressure Switch Input Malfunction. Applies to F-150, Mustang, Ranger, Taurus with hydraulic steering.

What causes P1651 on a Ford?

Failed pressure switch with erratic output Fluid intrusion into the switch connector Wiring fault in the switch circuit Air in the power steering system causing pressure spikes PCM input fault

How do I fix P1651 on a Ford?

Bleed air from the power steering system first Inspect the switch connector for fluid intrusion Watch switch state on a scanner through full lock turns Check fluid condition and level Replace the switch if its signal stays erratic

Code

P1651

Power Steering Pressure Switch Input Malfunction

Category: Powertrain - Computer and Auxiliary Controls
Severity: Check Engine Light
Applies to: F-150, Mustang, Ranger, Taurus with hydraulic steering
Related: No single generic twin. See OBD Codes List

Findings, check these first

Failed pressure switch with erratic output
Fluid intrusion into the switch connector
Wiring fault in the switch circuit
Air in the power steering system causing pressure spikes
PCM input fault

Standard procedure

Bleed air from the power steering system first
Inspect the switch connector for fluid intrusion
Watch switch state on a scanner through full lock turns
Check fluid condition and level
Replace the switch if its signal stays erratic

Code lookup

Type a code above, or start from a symptom or a common code.

Press / to jump to the box. Ford-enhanced powertrain, body, chassis and network codes. Generic P0xxx codes live on OBD Codes List.

Sources and review

Review: checked against the recorded source material.

OBDII.pro: P1651 Ford definition
live reference page (obdii.pro)
Supports: Ford-family meaning for P1651: PSP Switch Input Malfunction
Fetched directly. obdii.pro is a publisher independent of the engine-codes family.
P1651 FORD Code: Meaning, Causes, and Symptoms | OBD2 Codes
live reference page (obd2-codes.co)
Supports: Ford meaning for P1651: Power Steering Pressure Switch Input Malfunction
Fetched directly. obd2-codes.co phrasing matches the engine-codes family, so it counts as one publisher.

Last updated 2026-09-04.

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