P0504
0 owner reports and 41 manufacturer filings across 11 model years from Ford, Mazda.
Where P0504 shows up
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2022 Ford F-250 Super Duty | Power Train | 4 | — |
| 2021 Ford F-250 Super Duty | Power Train | 4 | — |
| 2020 Ford F-250 Super Duty | Power Train | 4 | — |
| 2022 Ford F-350 Super Duty | Power Train | 4 | — |
| 2021 Ford F-350 Super Duty | Power Train | 4 | — |
| 2020 Ford F-350 Super Duty | Power Train | 4 | — |
| 2022 Ford F-450 Super Duty | Power Train | 4 | — |
| 2021 Ford F-450 Super Duty | Power Train | 4 | — |
| 2020 Ford F-450 Super Duty | Power Train | 4 | — |
| 2024 Mazda CX-90 | Service Brakes, Hydraulic | 3 | — |
| 2021 Ford EcoSport | Electrical System | 2 | — |
A model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.
What it gets filed under
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names P0504. Quoting the document number at a service desk is often the fastest route to a diagnosis someone has already written down.
- 01-001-24a2024-01-31 · Service Brakes, Hydraulic
- Some vehicles may exhibit check engine light turns on with DTC P0504:00 [PCM] (Brake switch circuit problem) stored in memory. This may be caused by the PCM incorrectly reading the brake switch input. To eliminate this concern, the control software of the PCM has been modified.
- 01-001-242024-01-02 · Service Brakes, Hydraulic
- Some vehicles may exhibit check engine light turns on with DTC P0504:00 [PCM] (Brake switch circuit problem) stored in memory. This may be caused by the PCM incorrectly reading the brake switch input. To eliminate this concern, the control software of the PCM has been modified.
- SA-062-232023-10-16 · Electrical System
- Some customers may experience a "Push Button Start Malfunction. Have the Vehicle Inspected" warning message and the following DTC(s) may be stored. C0040:24 - Brake switch (No.1 signal) circuit malfunction P0504:00 - Brake switch system: Circuit malfunction
- SSM 508642022-06-16 · Power Train
- Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the vehicle will not shift out of park (P). Diagnostic trouble codes (DTC) C0040 and/or P0504 may also be present. Reference TSB 22-2044 to make sure that no water or corrosion is present in the battery junction box (BJB). If Pinpoint Test A: Brake Shift Interlock in Workshop Manual (WSM), Section 307-05 leads to a concern with cir
- SSM 508482022-06-14 · Power Train
- Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the vehicle will not shift out of park (P). Diagnostic trouble codes (DTC) C0040 and/or P0504 may also be present. Reference TSB 22-2044 to make sure that no water or corrosion is present in the battery junction box (BJB). If Pinpoint Test A: Brake Shift Interlock in Workshop Manual (WSM), Section 307-05 leads to a concern with cir
- TSB 22-20442022-02-16 · Electrical System
- Some 2020-2022 F-Super Duty vehicles may exhibit a condition where the engine will not turn off and/or have various electrical symptoms including a dead battery, horn stays on and no crank/no start. The vehicle may also have an illuminated anti-lock braking system (ABS) indicator with diagnostic trouble codes (DTCs) C0020 and U3003 in the ABS module. The vehicle may not shift out of park (P) and/o
What P0504 means
Source: SAE J2012 / OBD-IIP0504 sits in the generic range of the OBD-II standard, so it means the same thing on every vehicle sold in the United States — but WhichTrim does not carry a definition for it and will not invent one. What is on this page is the record: who named it and on what.
A stored code names the test that failed, never the part that caused it. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.
Common questions about P0504
Source: NHTSA files and the OBD-II standardCan I keep driving with P0504 stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light generally means the fault was logged and the vehicle is in a reduced-risk mode; a flashing light means stop soon, because a misfiring engine can destroy a catalytic converter in minutes. The safe read of this page is the mileage and the components, not permission.
Does a code mean the car is recalled?
No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.
Why do the counts here differ from other sites?
Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.
Will clearing the code fix it?
Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.