Backing out of my garage today, there was a squealing noise when I put on the brakes. Once I put it in drive, it went away even when I put the brakes on going forward . Parked and went in the store only to hear the squeal again when I backed out of the parking spot. My son did a test with the car, backed up and heard the squeal when he put on the brakes but when he drove in reverse without hitting the brakes the squeal was still there but very slight. He thought it was the brakes until he heard it while backing up with his foot off the brake. Any ideas what this is?

 

What year and model?

It still may be the brakes.
1. The brake pad wear indicator is only on one edge of the inner pad. There is no wear indicator on the outer pad.

2. If the pads are wearing down to where the indicator is, it can make noise even if you don’t step on the brake pedal. The Honda calipers are a floating type (sliding), it moves in and out relative to the rotor and has one only on the inboard side of the rotor. As your pads wear, the piston extends out closer to the rotor. When the pads are really thin and almost completely worn, the caliper will hold the pad close enough to cause the wear indicator to make noise even if the brakes are not applied, especially if there is uneven pad wear on one side. Initially, the brake noise from the wear indicator may not always make noise even if you don’t apply the brakes, as the wear indicator may not always be in contact with the rotor. Eventually, if the pads are not changed, it will make noise almost all the time.