1. Rear Fenders

One of the first areas to check is where the end of the rear bumper meets the rear quarter panel at the rear wheel opening.  Its at this point where rust begins to form as bubbling paint.

Look for the bubbling paint on both sides of the car.  This is one of the most common areas for all Mazda 3’s.

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2. Reverse / Backing up Lights

An area that isn’t obvious is under the bottom-corner of the reverse light lens located on the trunk lid or hatch.

Again, if you find the rust on one reverse light, there is a very good chance that it is on the other as well.

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3. Center Third Brake Light

Also on the trunk lid, look for bubbling paint around the third brake light.

This area is very common on Mazda3’s.

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4. Inner Fender Lip

The inner fender lip is stamped to provide not only a clean wheel well opening, but also provides strength and stability.

This area gets pelted by road debris spinning off your tires with everyday driving.  Because the paint in this area has no protection it easily gets chipped and rust easily forms.

Clean it well and inspect carefully.  This happens mostly on the rear wheel wells as the front is protected extensively by the plastic inner fenders.

5. B – Pillars

Pillars are the vertical support that forms the greenhouse of an automobile.  The B Pillar is the pillar located between the rear of the front door and the front of the rear door.  For more information on Pillars click here.

This area is the least obvious of all the suspect areas on your Mazda3 as it is covered by an adhesive vinyl trim sheet.  Rust actually starts to form underneath the vinyl and appears as a fairly faint bubbling vinyl.

This forms on both sides of the car and is best to inspect under day light or a well lighted area.  You will see in the photos below from the same car that on one side it is easy to spot and on the other it takes careful inspection.