Break sensor rear brakes

I took my honda accord 2007 to the dealer because I heard an intermittent rattle squeak coming from the rear left of my car. Pressing on the brakes had no relation to the noise stopping or starting although the noise sounded as though it could have been coming from the wheel.

The dealer told me that it could be the break sensor and they should do a brake inspection. I said ok and they did. He reported that the front brakes were not in need of pads but the rear were. Ii was surprised that the rear brakes went before the front. I am in hilly San Francisco with hills and the car has 19K miles on it. I had a 2004 that had no similar noise that preceeded need of brake pads.

I cannot find information anywhere on how the brake sensor works and if it does indeed let one know that the brakes need pads by giving off an intermittent weird noise. Shouldn’t there be a warning light?

My questions are:

Was this noise really a brake sensor noise?

Is it normal for rear brakes to go bad before the front.

Could this noise have been a faulty caliper knocking around which may have been covered by warranty?



Any help in my understanding would be greatly appreciated.



N R

Normally, front brakes do need to be replaced much sooner than rear brakes, but it is possible for the rear brakes to need replacement first, particularly if they have been dragging. 19k is unusually early for replacement of front or rear brake pads.

The noise of a brake sensor is usually compared to a cricket chirping, and this noise is heard when the brake pads are worn and are just about ready to start damaging the brake rotor. However, that noise stops when you apply the brakes. Some cars (BMW is the only one that comes to mind) do have a warning light for brake pad wear, but on most cars you get only an auditory warning.

You implied that you had your rear brake pads replaced, but you did not actually say that they were replaced. Were they replaced?
You also did not tell us if the noise has actually gone away. Has it gone away?

The rear brake pads on my Honda needed to be replaced (60K) before the front pads (still OK at 90k). The rear brake pads on some cars are not very thick, which may be the reason they need replacement before the front pads.

The noise you heard may or may not have been the brake pad wear indicators. We can’t hear it, so it’s hard to say.

“Faulty caliper knocking around?” What does that mean?

Calipers, even when faulty, don’t “knock around.” You’re barking up the wrong tree.

For future reference, brake pad wear indicators make a screeching, or metallic rubbing noise that stops when you step on the brake pedal.

Calipers do “knock around” if one of the bolts holding them down falls out or wasn’t installed when the car was manufactured or the pads were previously serviced (at 19K? Not likely). Or if the bolts are loose. But those, and other brake related sounds including the wear indicators, will change when the brakes are applied and the post says that doesn’t happen.

On the cars I am familiar with, the wear indicator (I assume that is the dealer’s ‘brake sensor’) is a simple springy metal reed that rubs on the disk when the pads wear down enough for it to make contact with the disk. It makes a really annoying racket when you step on the brakes and put the reed in contact with the rotating disk. Simple, reliable, and add only a penny or two to the cost of the car.

Rear brakes will wear out fast if you sometimes drive with the parking brake on. That’s easy to do on many cars. It should light the brake light on the dash, but some dash brake lights are positioned such that some drivers can’t see them when sitting in their normal driving position.

I’d be inclined to think that any rear end rattle that doesn’t change when the brakes are applied is caused either by a bad wheel bearing, a problem with a shock absorber/strut, a sway bar, or by something bouncing around in the trunk.

A point. Locating sounds on a car is notoriously difficult. It’s not impossible that a sound that seems to be coming from the left rear is coming from someplace else entirely.

I had a '98 Volvo wagon V70XC that went throught rear brake pads much faster than the fronts. Not the norm, but some cars do use up rear pads faster than others.

Your Honda has the EBD (Electronic Brake Distribution) system.

How this works is, when the brake pedal is applied gently, the EBD system sets the brake bias more towards the rear brakes. If the brake pedal is pressed harder the bias is set more toward the front brakes. This then causes the front wheels to rotate at a slower rate than the rear wheels. The EBD system detects the difference in wheel rotation speed between the front and rear wheels and the EBD system applies the rear brakes so that both the front and rear wheel speeds are the same. This allows for more stabilty under all braking conditions.

People are use to seeing the front brakes wear out faster. But with the advent of ABS and STC on todays vehicles, on most vehicles the brake bias is to the rear wheels, so the rear brakes wear out faster.

Tester

Thank you for your reply.
I did have the rear brake pads replaced. I haven’t heard the noise again, but it has only been a few days and the noise had been intermittent. I will continue to listen for it.
The noise I initially heard wasn’t what I would call a chirping.
thanks again,
Nancy