I am having what I think are problems with the front brakes on my 2003 accord ex-l. The car has 183,000 kms on it.

I was on vacation for 2 weeks and left the car in the driveway and didn't drive it for 2 weeks. When I got back and started the car up it wouldn't start on the first turn (as it always did). I waited a few seconds and turned the engine over again and the car started no problem.

When I started driving and pressed the brakes for the first time to slow down the front brakes began to pulsate and buzz as if the ABS brake system was deploying. From then on whenever I was pushing the brakes to slow down the ABS would deploy (or at least it felt like it) when I was roughly between 60 and 20 km/hr. There are no ABS or brake warning lights on and this has never happened before.

I took the front and rear wheels off. The rear calipers are two years old (Honda parts) and were not seized and sliders were working properly. The rear rotors and pads (Honda parts) were 3 months old and were good. The front rotors and pads were a little older and looked good to me. The front calipers (Honda parts) are 2 years old and were not seized and sliders were working properly. I noticed the back left speed ring had cracked and was loose so I took off the hub and cleaned the rust off the speed ring and hub and tack welded it back onto the hub. After putting the wheels back on and testing, the ABS and brakes would still deploy as described.

I took it to a mechanic and he checked out the computer codes. There were no codes found, the abs sensors were ok and all wheels were stopping at the same speed. He said the right front rotor had a high spot and said the right front pads were low. He suggested replacing the front rotors and pads thinking this could solve the problem. It didn't. He isn't sure what is causing the problem. I don't want to take it to the dealer because it will cost me an arm and leg to fix it I'm sure. But it seems like my only hope now.

Does anyone know what could be causing this?

I should also mention that I have had both front axles replaced about a year ago. Before I had this done, at about 90 to 100 km/hr I was getting a vibration in the front end of my car as I accelerated which felt almost like the car was jumping around. After my mechanic checked it out and replaced the front axles this solved the problem. I only mention this now because I am getting another shimmy like this at about 50 to 70 km/hr and sometimes in the 100 km/hr range again as I accelerate. It's not as noticeable as before but it's there. I'm not sure if this is related.

 

Can I assume you'd recognize the difference between ABS actuating vs. pulsating brakes because of rotors? I'm thinking that it might be simply rust on the rotors from being parked for 2 weeks. Normally that solves itself as you use the brakes. Occasionally the rotors clean up unevenly, especially if you clamp down the brakes on hot rotors after aggressive braking.

If it's actually the ABS working, then that broken pulser ring is my first thought. Even tacked back together, the notches might be uneven right where it's cracked.

 

A faulty ABS modulator is suggested, but should generate a code. A faulty ABS controller is also possible. This problem may require someone very experienced w/ ABS issues to diagnose. I suspect it will be difficult to get any help on this issue, except for parts replacement.

It might be preferable to drive the car for a while. Sometimes problems resolve themselves.

CV axles are notorious for repeat failures, even "out-of-box" if they are AZ, ORiellys, etc inexpensive parts.

good luck

 

Thanks for the replies so far guys.

JimBlake: Yes, this is definitely the ABS brakes deploying when the brake pedal is pressed. Whenever it's pushed I get a steady electronic buzzing from the front of the car and a uniform pulsing feeling from the brake pedal no matter what speed I'm at. I think a warped rotor would give me a different pulsing feeling from the brake pedal depending on the speed I was at and no electronic buzzing. Also, the rear rotors/pads are only 3 months old and the front rotors/pads are now less than a week old. I suppose it's possible that they could be warped, but I don't think it's likely. In terms of rust on them, the wearing surface of the rotor looks clear and shiny.

I wasn't able to get the speed ring pushed completely back together when I put it back on. So there is probably a 1/32 to 1/16" gap made by the crack through the speed ring. Maybe this is enough to cause the ABS brakes to still kick in?

TexasHonda: I've been driving the car for 2 weeks now and still the same ABS deployment issue. Do you think my vibration problem is the front axles gone again? They were replaced with OEM parts when I did them. Do you think the perodic vibration in the front end could be caused by loose engine mounts?

 

The cracked/repaired pulser ring may be generating a false signal that "fools" the ABS controller into actuating ABS modulator. I would get a new hub assy to replace.

If the replacements are Honda parts, it's unlikely they have failed again so soon. You might inspect the front and rear motor mounts for damage.

good luck

 

Honda no longer used the ABS tone ring (pulser) on the axle like previous generation Accords. Some axles won’t even have it. The magnetic encoder is incorporated into the wheel bearing. The ABS system uses sensors to pick up a signal from the magnetic encoder on the wheel bearing. Even if the axle has an ABS tone ring on it, it may not serve any functional purpose.

 

It was on a rear wheel where the tone ring was damaged. I found part in the shop manual on the wheel bearing assy.

good luck

 

Yes, the rear hub bearing assembly has the pulser. I first thought he was referring to the front axles, since he mentioned the axles. I re-read his original post and now see his part regarding the back left.

 

Thanks for the help guys. I'm going to buy a new hub assembly next month (stretching my finances) and put it on and see if that fixes the problem. I'll post back on what I find out.

 

Hey guys just wanted to let you know that I replaced the hub assembly and this completely fixed the issue with the ABS brakes deploying. I guess that small crack left in the speed ring was enough to keep setting off the ABS brakes.