C1446: Brake switch circuit failure (Ford)
C1446 brake light switch circuit (Ford)
Severity: Severity not verified — if the car runs badly, have it inspected
The sources say the ABS module saw a brake switch circuit fault but do not rate drive safety; brakes are safety-critical, so have it checked.
C1446 in short
On Ford vehicles C1446 is a brake switch circuit fault seen by the ABS module. On one 2006 F-250 Super Duty the brake lights worked and the fault was the master cylinder low fluid switch. ABS may be off, so have a shop check it.
The ABS module watches a brake switch signal to know when the pedal is pressed. C1446 means that circuit is faulty, for example a switch that stays closed or drops out.
In the one case we read, a 2006 F-250 Super Duty set C1446 even though the brake lights worked; the master cylinder low fluid level switch that feeds the ABS module was failing intermittently. That is one owner-reported case, not a rule.
Brakes are safety-critical, so this page gives no do-it-yourself steps.
Pick your make
C1446 is a manufacturer-specific code: its meaning depends on who built the car.
Other makes: meaning not verified. Check with a scan tool that reads manufacturer definitions.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Brake switch or its wiring
Possible — needs testing- Why it ranks here
- TaT lists C1446 as a brake switch circuit failure from a switch signal that is implausible, such as stuck closed.
- What would change this
- Rises if the switch signal reads wrong on a scan tool. Falls if it follows the pedal correctly.
Cause 2: Master cylinder low fluid level switch (F-250 Super Duty)
Possible — needs testing- Why it ranks here
- One owner-reported 2006 F-250 Super Duty case traced C1446 to the master cylinder fluid level switch.
- What would change this
- Rises if brake lights work and the fluid level switch circuit is intermittent. Falls if the fluid level switch tests fine.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Ask a shop to read the ABS codes and test the brake switch circuit, including any master cylinder fluid level switch.
Warning:Brake faults are safety-critical; leave diagnosis and repair to a qualified shop.
IfThe brake switch signal is wrong or intermittent
It meansThe switch or its wiring is suspect.
IfThe brake lights work but the code returns
It meansCheck the fluid level switch circuit.
Points to: Master cylinder low fluid level switch (F-250 Super Duty)
Symptoms
- ABS lamp on
- Brake lights stay on or do not work
- Red brake lamp on or pedal feels wrong Gets more serious: stop and have it checked.
How to fix
This is a safety-critical system, so we explain the code but don't give repair steps. Have it inspected by a qualified technician.
On your vehicle
FordYour car
2006 · F-250 Super Duty
Possible — needs testingOne owner-reported 2006 F-250 Super Duty case traced C1446 to the master cylinder low fluid level switch while the brake lights worked. Single case, not a bulletin.
Related codes
No curated relationships for C1446 yet.
C1446 questions
Is it safe to drive with C1446?
Normal braking usually works but ABS may be off. Get the brakes checked soon, and stop if the red brake lamp comes on or the pedal feels wrong.
Sources and review
- Code C1446 brake light switch circuit fault (2006 Ford F-250 Super Duty)
- C1446 fault code: Brake Switch Circuit Failure
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error