What does P1793 mean on a Ford?

P1793. Ignition Supply Malfunction. Applies to F-150, Explorer, Ranger, Mustang.

What causes P1793 on a Ford?

Blown ignition fuse Failing ignition switch Corroded supply splices Voltage drop in the ignition feed Aftermarket devices overloading the circuit

How do I fix P1793 on a Ford?

Check ignition fuses under load Voltage-drop the ignition feed Test ignition switch outputs Remove aftermarket loads and retest Repair the supply circuit

Code

P1793

Ignition Supply Malfunction

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

Findings, check these first

Blown ignition fuse
Failing ignition switch
Corroded supply splices
Voltage drop in the ignition feed
Aftermarket devices overloading the circuit

Standard procedure

Check ignition fuses under load
Voltage-drop the ignition feed
Test ignition switch outputs
Remove aftermarket loads and retest
Repair the supply circuit

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: qualified. Read the source limits below.

OBDII.pro: P1793 Ford definition
live reference page (obdii.pro)
Supports: Ford-family meaning for P1793: Intake Air Volume Circuit Malfunction
Fetched directly. obdii.pro is a publisher independent of the engine-codes family.

Last updated 2026-09-06.

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