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A piece of wiring fell off... brake acting weird

Yesterday, as I was driving (more like inching forward) on the I-278 in heavy bumper to bumper traffic, suddenly I heard a sound, then as I braked to a stop, the car began to roll slowly backwards!

Normally, when the car stops, I can feel the inertia gently push the car backwards, and it catches on the brake and stops completely. This time there was no catch, and the car slowly rolled backwards. I pressed on the brake as hard as I could and it stopped before hitting the car behind me.

It happened like three more times before I reached my destination. It did not happen everytime.

When I parked I noticed a piece of plastic and wire by my feet. It seems it had fallen off (the sound I heard). See attachment.

I showed to my friends. No one knew what it is. I then drove to the dealership, which wouldn’t see me because I need an appointment on a Sunday… So I drove all the way home and weirdly enough, did not again encounter the backward problem.

I will not drive again until the weekend and will take it to my local dealership first thing on Saturday. Just wondering if anyone has an idea what this could be.

I missed the make and model.

(Normally, when the car stops, I can feel the inertia gently push the car backwards, and it catches on the brake and stops completely. This time there was no catch, and the car slowly rolled backwards.)

This statement concerns me. If you stop the vehicle and keep the brakes applied it should not roll at all. If you are on an incline and don’t have enough pressure on the brake pedal yes it could move otherwise no.

That part doesn’t look brake related at all. It really doesn’t look car related unless the car is very, very old.

Brakes respond pretty simply, they either stop the car or they don’t. You say they do. Great, that’s what they are supposed to do.

What’s the problem again? @VOLVO_V70 has a good comment… not sure we understand the inertia-catch.

The inertia sounds like the front suspension compressing when braking and rebounding once completely stopped. Don’t most cars do that?

You heard the sound and the brakes started mis-behaving on the highway. Then you drove a number of miles, got out of the car and found a piece of metal on the street? Why would you think it is off your car? If something fell off, it would be on the highway miles away, not where you parked the car.

I agree with Rod_Knox. I can feel that also.


The piece was INSIDE the car by my feet, where the brake and accelerator are.

If this piece isn’t from my car then the only thing I can think of is that when I changed my oil the dealership left it in there by accident. (2 weeks ago)

What make, model, age, and miles for your car?

That might be part of a switch that senses when your brakes are applied. Do your brake lights work?

On some vehicles – I think this applies to manual transmissions – when you come to a stop the brakes automatically engage to prevent you from rolling backward. Useful for example if you live in San Francisco and stop on a steep uphill. That way when the light turns green you don’t roll backwards into the car behind you while starting out. The rest of us have to apply the emergency brake for this.

I think though that this feature is used by Subaru mostly. Does your owner’s manual say your CRV has it too? If so, that could be the problem.

The only other thing I can think of – besides the good ideas above – is one time on my Corolla something like this happened. My knee knocked up against the dash while entering the car, a piece of plastic fell down, and after that the engine wouldn’t crank. No rr rr rrr sound. That turned out to be that the dealership had installed a security device to prevent the car from being stolen while it was parked on their lot. Some kind of gadget was needed to be plugged in apparently to get the car to crank. They failed to remove the whole thing when I purchased the car, instead only disabling it, and the knee-event damaged it enough to prevent cranking. So maybe something like that, a dealership security device.

Is the brake pedal going further down (closer to the floor) than usual when this happens?