Mazda bulletin 04-001-23b
What it saysFront Brake Noise Symptom 1: Some vehicles may exhibit a click noise when first moving forward or reverse from a stop OR when first applying the brakes while moving forward at slow speeds. NHTSA’s full summary ↓
Mazda filed this with NHTSA as a service bulletin dated Sep 13, 2023, received Oct 4, 2023, about the service brakes. It names 9 model years (2016–2024). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationFront Brake Noise Symptom 1: Some vehicles may exhibit a click noise when first moving forward or reverse from a stop OR when first applying the brakes while moving forward at slow speeds. This is caused by deteriorated grease between the brake pads and the shim, the front brake pads move upward/downward along with the brake rotors during brake application. When the vehicle moves or the brakes are applied the next time, the front brake pads move to the other side, which causes a click noise. Front Brake Noise Symptom 2: Some vehicles may exhibit the brakes having an unusual noise or vibration when applying the brake. This is caused by rust on the brake disk plateâs surface. Rear Brake Noise Symptom 1: Some vehicles may exhibit a squeak noise from the rear brakes while braking lightly and occurs more frequently when driving at slow speeds. The noise is caused by poor contact between the guide plate and the mounting support. To eliminate this concern, the material of the pads has been changed to copper-free and the specification of the shims has been changed to a coated spring with tape. Rear Brake Noise Symptom 2: Some vehicles equipped with an electric parking brake (EPB) may exhibit a grinding noise from the rear brakes when braking. This may be caused by the rear brake pads not having the capability to remove the rust from the rear brake discs. The red rust accumulated on the discs is exposed to high temperatures during braking, and consequently the rust turns black. As the black rust is too hard to be removed by the brake pads, the rust progress is accelerated, resulting in the grinding noise.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 04-001-23b | Service bulletin | Sep 13, 2023 | 10243545 | PDF, 313 KB |
What the document itself lists
Parts the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| KGY0-33-28Z | PAD SUB SET, FRONT CALIPER | — | eBay Motors → |
| K0Y1-33-29Z | ATTACHMENT (SHIMS), PAD-FRONT (W/O | — | eBay Motors → |
| TAY0-33-28Z | PAD SUB SET, FRONT CALIPER (W/ TURBO) 1 -- ATTACHMENT (SHIMS), PAD-FRONT (W/ | — | eBay Motors → |
| L2Y6-33-29Z | ATTACHMENT (SHIMS), PAD-FRONT (W/ | — | eBay Motors → |
| KD45-33-251 | FRONT PLATE DISC (W/O TURBO ) 0 or | — | eBay Motors → |
| TK78-33-251B | FRONT PLATE DISC (W/ TURBO) 0 or | — | eBay Motors → |
| TKY8-33-28ZB | PAD SUB SET, FRONT CALIPER (DIESEL) 1 --2018 CX | 5 | eBay Motors → |
| KBY6-26-43Z | PAD SET, REAR CALIPER 1 With Attachments | — | eBay Motors → |
| K011-26-251C | REAR PLATE DISC 0 or | — | eBay Motors → |
| KBY6-26-48Z | — | — | |
| KBY6-26-49Z | can be used in | — | eBay Motors → |
Read by machine from the document NHTSA serves (6 pages), read Sep 30, 2026. A part number is shown only where it matches Mazda’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote. Listings and prices on eBay Motors are the seller’s.
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The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 9 model years this bulletin names have filed 1,726 complaints with NHTSA since 2015. 164 of them name Service Brakes — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
On the 2016 Mazda CX-5, the 51 owners who gave an odometer reading for Service Brakes reported it at a median of 28,350 miles. That figure is one model year’s, not the whole range this bulletin covers — medians from different model years are not averaged.
The contact owns a 2016 Mazda Cx-5. The contact stated that while attempting to stop at 20 MPH, the brake pedal was depressed and failed to respond. The contact stated that while the brake pedal was depressed, the vehicle accelerated continuously. The vehicle was able to be stopped after the brake pedal was depressed to the floorboard.
2016 Mazda CX-5 · Service Brakes · filed with NHTSA Dec 23, 2015 · ODI 10811984
On April 16, 2022, around 6:45PM, I drove my new Mazda CX5 (@ 3500 miles) into our church parking lot and turned right down the first row of cars. It was light out and the weather was pleasant. I turned right into a parking space with my foot on the brake. The car was facing and perpendicular to a sidewalk that was about 10 feet away.
2021 Mazda CX-5 · Service Brakes · filed with NHTSA Apr 27, 2022 · ODI 11462431
I was parked at a fast food restaurant that had an outdoor kiosk for payment. I got out of my car to pay and got back in. After about a minute or two my car accelerated forward, going over a sloped curb and down a short low grade hill, hitting a pole. I was confused to how the car would go forward because I was in park the whole time
2020 Mazda CX-5 · Service Brakes · filed with NHTSA Apr 1, 2021 · ODI 11405931
In depth: 2016 Mazda CX-5 brake problems →
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the service brakes
Source: same model, same component group9 other manufacturer communications filed against the Mazda CX-5 under the same component group (service brakes), newest first. The eight newest are listed; the rest are on the Mazda list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| SA-029-26 | Service bulletin | Apr 21, 2026 | This Service Alert supersedes the previously issued SA listed below: The changes are noted in Red. SA-011/24 02/12/24, 06/06/24, 07/29/24 DE… |
| SA-055-25 | Service bulletin | Nov 26, 2025 | Some vehicles exhibit brake related concerns such as brake noise, brake judder or brake dragging. If you encounter a customer complaint for… |
| SA-016-24c | Service bulletin | Oct 5, 2024 | Some vehicles exhibit brake related concerns such as brake noise, brake judder or brake dragging. If you encounter a customer complaint for… |
| SA-016-24b | Service bulletin | Aug 21, 2024 | Some vehicles exhibit brake related concerns such as brake noise, brake judder or brake dragging. If you encounter a customer complaint for… |
| 04-003-24 | Service bulletin | Jul 9, 2024 | Front Brake Noise Symptom 1: Some vehicles may exhibit a click noise when first moving forward or reverse from a stop OR when first applying… |
| SA-016-24a | Other | Jun 7, 2024 | Some vehicles exhibit brake related concerns such as brake noise, brake judder or brake dragging. If you encounter a customer complaint for… |
| SA-016-24 | Service bulletin | Mar 8, 2024 | Some vehicles exhibit brake related concerns such as brake noise, brake judder or brake dragging. If you encounter a customer complaint for… |
| SA-060-23 | Service bulletin | Oct 11, 2023 | Permanent updates to these procedures in the WSM are in progress and once complete this Service Alert will be unpublished. While these updat… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Mazda, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Mazda 04-001-23b a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the 04-001-23b repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every Mazda warranty extension on file lists the ones Mazda has filed.
Which vehicles does 04-001-23b cover?
The manufacturer filed it against 9 model years: 2024 Mazda CX-5, 2023 Mazda CX-5, 2022 Mazda CX-5, 2021 Mazda CX-5, 2020 Mazda CX-5, 2019 Mazda CX-5 and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.