Volvo 850 GLT 1995 - ABS Brake Groaning

mikemmb · Post by **mikemmb** » 19 Mar 2007, 12:24

Hi,
I have a really strange problem!
At low speeds my brakes make a groaning sound and if you put your foot on the brake pedal you can feel a very high frequency vibration through the brake pedal.
It does not always happen, but when it does, it's always at low speeds, with or without the brake pedal being pressed.
A sharp tap on the brake pedal clears it for a short time.
Brake performance seems normal.
Not sure if it is the ABS module or a wheel sensor (or something else?).
It is driving me mad ....... has anyone else had this or can offer a cure?
Thanks Mike.

Post by **MadeInJapan** » 19 Mar 2007, 18:00

Sounds like a wheel sensor or even possibly a sticking caliper...try cleaning the sensor and checking to see if your caliper sticks and see if this clears the problem up.

mikemmb · Post by **mikemmb** » 20 Mar 2007, 14:39

Hi,
Is there any way of testing the sensors to see if they are working OK?
Mike

Post by **billofdurham** » 20 Mar 2007, 16:12

Your vehicle is from around the time when Volvo switched from OBD1 to OBD11.

If you have the OBD1 system, in the engine compartment, you can read fault codes using module A socket 3.

For a full how-to download the manual at the top of this forum then open the .pdf file 'Anti Lock Braking System and Traction Control'

Bill.

DanK · Post by **DanK** » 23 Mar 2007, 11:56

I have a '98 S70 GLT and have the same issue. Once the grinding stops, the ABS and Tracs lights come on. Codes say it is the front and back right sensors. Could it also be my ABS module? The Volvo dealership says yes. Any thoughts? Thanks.

mikemmb · Post by **mikemmb** » 23 Mar 2007, 16:06

Hi,
I do not (yet?) get any warning lights so not quite the same symptoms as you DanK. You mentioned that your brakes "Grind" .... the sound that I get is not a grinding sound, it really is a very high frequency, low pitch sound that is more of a groaning noise (like waking up with a big hangover and realising you have to go to work!!)

My car is the OBD11 type, so will I need a fancy code reader??

Mike

Post by **MadeInJapan** » 23 Mar 2007, 19:11

mikemmb wrote:Hi,
I do not (yet?) get any warning lights so not quite the same symptoms as you DanK. You mentioned that your brakes "Grind" .... the sound that I get is not a grinding sound, it really is a very high frequency, low pitch sound that is more of a groaning noise (like waking up with a big hangover and realizing you have to go to work!!)

My car is the OBD11 type, so will I need a fancy code reader??

Mike

Sounds like a Wheel bearing to me...no code reader to diagnose this issue. Try putting your car up on jack stands and then the car in neutral...spin the wheels by hand and see if you hear anything like you get on the road. Also, you should note that bearings go strange things as they wear...turning and going straight the sound is different.

Post by **MadeInJapan** » 24 Mar 2007, 08:04

First time I've heard of this....wanna learn more about it...
Do you have a source for what you just quoted?