Ford Codes List

Ford-enhanced trouble code lookup
for Ford, Lincoln and Mercury.

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655 Ford-enhanced codes on file

Code
P1935

Fuel Additive Level Low (Diesel)

Category
Powertrain - Fuel/Air Metering
Severity
Check Engine Light
Applies to
Ford diesel models with additive systems
Related
No single generic twin. See OBD Codes List

Findings, check these first

  • Additive level below threshold
  • Normal consumption since last service
  • Slow leak in the system
  • Sensor reading slightly low
  • Missed top-off

Standard procedure

  1. Top off the additive tank
  2. Inspect for slow leaks
  3. Verify the sensor reads full after refill
  4. Reset the level monitor
  5. Confirm the code clears

Code lookup

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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: P1935 Ford definition

    live reference page (obdii.pro)

    Supports: Ford-family meaning for P1935: BRAKE SWITCH / SENSOR SIGNAL

    Fetched directly. obdii.pro is a publisher independent of the engine-codes family.

  • P1935 FORD Code: Meaning, Causes, and Symptoms | OBD2 Codes

    live reference page (obd2-codes.co)

    Supports: Ford meaning for P1935: Fuel Additive Level Low

    Fetched directly. obd2-codes.co phrasing matches the engine-codes family, so it counts as one publisher.

Last updated 2026-09-06.

Report a correction for P1935. Include your vehicle, the issue and a source if you have one.

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