Check ABS sensor on an Almera

congo_90

Hey all. Was driving the mothers Almera (06 SXE) last night and had a run in with some fool over taking a car on a bend on a country road! anyways naturally I had to brake or be broken. The wheels locked up slightly and I had no control over the car for a brief moment until it regained grip. I was not speeding 65-70km/h (speed limit 80).
Thing is I didn't feel the ABS pulse on the pedal. The tires on the front are cheapy eco tires (her choice not mine). the stock tires (great grip) are still on the back.
AFAIK the Almera has 4 wheel ABS so could the 2 back tires not skidding cause the ABS to sit still or is it a clogged sensor on the wheel?

I'd like to rectify this problem before it gets out of hand.
Cheers for all advice!

for the record, near miss was on the lucan-dunboyne road near the westmanstown bridge if anybody was there at that time

Seth Brundle

I presume if there was a fault then a light would come up on the dash.
It could be anything or nothing - get it diagnosed!

congo_90

*edit*
No fault light showing on the dash either before or after! tis a tad worrying. Might send it into the dealers at the end of the month.
I read somewhere that brake dust and road dirt can inevitably clog a sensor on the brakes which won't throw up a warning. Ever hear of this before I go about taking a look under the calipers?

ianobrien

If I read it right, the wheels locked for a moment, and then were not locked. Did you change the pressure on the brake pedal during the incident? If not, I'd say that the ABS is working, and the reason the wheels were at first locked, and then not locked was because of the ABS.

I will admit that the poor grip of the tyres may not have helped and may have confused the ABS system, and that in my Almera (05), the vibration in the pedal doesn't start straight away, but it does vibrate.

ABS works by sensing a difference in wheel speeds when brakes are applied. If there is a difference (ie wheel locked), it will reduce the pressure until the speed of the wheel matches the rest. The wheel will lock for a moment, and the vibration through the pedal is because the system is varying the pressure being applied to the brake.

Cookie_Monster

Slightly off topic but when did Almera's get ABS as standard. I have an 03 and am fairly certain there's no ABS. The car has skidded under heavy braking numerous times even with brand new tyres:( Have never felt any pedal feedback either

EPM

From 05 on when they got the 16 inch wheels as standard

ianobrien

Cookie_Monster wrote: »

Slightly off topic but when did Almera's get ABS as standard. I have an 03 and am fairly certain there's no ABS. The car has skidded under heavy braking numerous times even with brand new tyres:( Have never felt any pedal feedback either

I'm fairly certain that if the Almera has drum brakes at the back - no ABS

Mr.Diagnostic

ianobrien wrote: »

I'm fairly certain that if the Almera has drum brakes at the back - no ABS

Dunno about the Almera but plenty of cars with rear drums have ABS.

mickdw

First thing to do is take the car to a quiet bit of road and try to skid it. If it skids to a halt...... no abs fitted or faulty abs. If it works, well all is good.
Generally faulty ABS should turn the light on. Does it come on on startup for a few seconds?
If you have a fault, it wouldnt have anything to do with tyre grip in reality. Differing rolling radii could cause it though.
If any tyre loses grip too easily, it should activate the abs, not cause it to malfunction.

congo_90

ianobrien wrote: »

If I read it right, the wheels locked for a moment, and then were not locked. Did you change the pressure on the brake pedal during the incident? If not, I'd say that the ABS is working, and the reason the wheels were at first locked, and then not locked was because of the ABS.

No i never changed the pressure on the pedal as that voids the use of ABS. My own car doesn't have ABS and I'm familiar with both cars fairly well. It seemed to lock up until the car slowed down at which point The hazard was just avoid-able.

ianobrien wrote: »

I'm fairly certain that if the Almera has drum brakes at the back - no ABS

Almeras from 05 upwards were 16 inch wheels + 4 discs afaik (at least on this model)

mickdw wrote: »

First thing to do is take the car to a quiet bit of road and try to skid it. If it skids to a halt...... no abs fitted or faulty abs. If it works, well all is good.
Generally faulty ABS should turn the light on. Does it come on on startup for a few seconds?
If you have a fault, it wouldnt have anything to do with tyre grip in reality. Differing rolling radii could cause it though.
If any tyre loses grip too easily, it should activate the abs, not cause it to malfunction.

See thats the thing. I took it to a quiet spot both in the wet and dry and at 50km/h went hard on the brakes. The ABS didn't ever pulse on the pedal but the wheels never locked either Having Said that, yes the ABS light does come on (flashes as tester) at ignition start up which is normal thankfully. As it's her car she'll be reluctant to repair until it breaks apart so I might take it for a few days and have a dealer suss it out as the airbag needs servicing anyways.

See it's unusal as I've driven other cars where the ABS was very sensitive. Maybe its just more suttle in an Almera? I learnt to drive in this car and when it had it's stock tires safely performed an emergency stop in traffic (albeit I was rear ended by a punto with no ABS).
I've narrowed it down to a sensor not registering the fault to the ECU or just the ECU can't compensate for the tires (which would defeat the purpose of the ABS).
Either way seems no-one has heard of a clogged ABS sensor?
I'll keep yas posted

Voodoomelon

ABS is standard on all European cars since July 2004, however its a bit of a grey area for Japanese/Korean imports. I'd say your Almera probably does have ABS though.

Darragh29

Does the ABS light come on when you put the key in the ignition and turn to accessories??? Does it go out then when the engine is started. If these two events are happening, then it is unlikely you have a problem. If in doubt, head to an empty car park or a remote location with a bit of dust/loose gravel on the road and drive the car and hard brake. If the car starts skidding, you sould feel the ABS modulating the brake pressure to unlock the wheels.

congo_90

Darragh29 wrote: »

Does the ABS light come on when you put the key in the ignition and turn to accessories??? Does it go out then when the engine is started. If these two events are happening, then it is unlikely you have a problem. If in doubt, head to an empty car park or a remote location with a bit of dust/loose gravel on the road and drive the car and hard brake. If the car starts skidding, you sould feel the ABS modulating the brake pressure to unlock the wheels.

All as abve happens, ABS check light at accessory stage (for testing) stop illuminating after approx 8 seconds then nothing more.. There's a gravel car park up the road. a bit bumpy but might give it a go tomorrow and see how it performs. Again, maybe the abs feedback isnt so sensitive as is in say a ford focus? also in a audi A8

Will re-post results tomorrow evening

congo_90

Hey sorry been too busy to get on this lately. Ran a test tonight on my way home. The ABS did actually work. The feedback on the pedal just felt a little odd because i'm used to a more pulsing type pedal but still it worked.
That leaves road surface v's tyres. I'd put it down to the tires as I said earlier they're economy tyres so grip isn't great imo.
Good thing I didn't go pulling the car apart Cheers for all who did reply anyways.