Owners of other Mazda vehicles such as the CX-5, CX-3, CX-30, MX-30, CX-8, Mazda8 (MPV), MX-5 Miata, Mazda2 (Demio), Mazda3 (Axela), Mazda6 (Atenza) and Mazda5 (Premacy) may also find these DIY instructions to be helpful.

This 2019 CX-9 AWD was equipped with low profile mini blade electrical fuses.

Please check the fuses in your SUV to verify the correct type before purchasing new ones.

No tools are required to access and replace the fuses.

There should be a white plastic fuse puller tool included on the underside of the cover for the engine bay electrical block.

If the tool is missing, you could use needle nose pliers with rubber insulated handles.

The first two steps are to open the hood and move to the right (driver side) of the engine bay.

Push in the release tab on the rear edge of the fuse box cover situated near the suspension tower.

Turn over the cover to view the fuse location diagram. There is also another fuse location diagram in your owner's manual.

The underside of the cover should be equipped with a white plastic fuse puller tool and a few spare fuses.

Locate the square shaped access cover near the foot rest pedal (also known as the footrest or "dead" pedal).

Insert your fingers into the opening on the right side of the cover (closer to the brake pedal).

Gently pull out the access cover.

Set the access cover aside in a safe place.

Place the jaws of the fuse puller tool over the old fuse that you'd like to check or change.

Pull the old fuse straight out of the socket.

To check the condition of the old fuse, hold it up to a light bulb.

If the thin metal strip or "band" in the translucent plastic center of the old fuse appears to be burnt, broken and shriveled up, the old fuse is most likely "blown" and should be replaced.

If the thin metal bar in the middle of the fuse appears to be intact, the old fuse is probably still in good working condition.

Push a new low profile mini blade fuse of the same amperage rating (e.g. 5A, 10A, 15A, 20 amps, etc.) straight into the socket.

Make sure the new fuse is fully seated in the socket.

If you would like to add a hard wired power source for any automotive accessories such as a Bluetooth audio adapter, radar / laser detector, an auxiliary gauge (turbo boost or transmission temperature), dash camera / dashcam or a GPS navigation unit, install an "Add-A-Circuit" Fuse Holder Tap (also known as a piggyback fuse holder).

If you suspect that a faulty relay is your issue, the easiest way to troubleshoot the problem is to just simply replace the relay with a new one of the same amperage rating.

If you have a digital multimeter tool, you can test the old relay.

To remove an old relay, grasp it with the needle nose pliers and carefully pull it straight out of its socket.

Re-attach the white plastic fuse puller tool to the underside of the cover.

Line up the plastic cover with the engine bay fuse box.

You should feel or hear the retaining clip "click" securely into place.

Double check that the cover is securely attached.

Push the access cover back into place.

Test the electrical component that you were having issues with such as the horn, A/C system, stereo, power windows, power door locks, tail lights, headlights, interior lights, power driver's seat, etc.

If you are still having the same electrical problem, there may be a shorted out wire or the component itself needs to be replaced.

Be sure to write down the fuse change in your vehicle's service records.

For more, please check out all of the 2016-2021 Mazda CX-9 DIY Repair & Maintenance Guides.