cossie abs ecu if theres a fault will it remember and do you need to disconnect the battery to reset?

Paul

 

anyone?

having probs with pulsing at slow speeds checked everything still no joy

Whats the story behind the bias valve at the rear and why was it moved to the front on later cars?

I'm running a 350 4 pot on front and 4x4 on rear if that helps any

Paul

 

Fault codes are reset on power off

Cant help you with the pulsing though, sorry !

 

the valve arragement was purely for heat issues

you've got the ones with the integral valve assemby and the ones with it split on the passenger side

plus you've got the orientation of the bits on the main block itself

the pulsing is probably more to do with the vavle assembly being blocked up, but i've no idea how to go about unblocking it other than finding a decent replacement

 

Cheers Si suppose you sold your abs fault thingy a long time ago?

Paul

 

its only done it since fitting the brakes and changing fluid

Starting to get to me a little

Paul

 

Actually no I didnt now that you remind me.

I will have a look in the shed for it later when I get home if you need to borrow it.


[this isnt a for sale advert]

 

how did you bleed the brakes then?
you may still have an air lock in the valve block
you do know that you need to have the ignition on at pos1 to prime the pump to pressureise the rear lines and then put your foot on the pedal to open the valve to let the fluid through don't you?

 

Yes mate i do

Simon i would be gatefull if i could borrow it again lol

Pm me when you find it thanks

Paul

 

Pedal pulsing and antilock action at low speeds (below 10mph?) means the ABS sensors are giving innaccurate information to the ECU, which is triggering the anti-lock system. The anti-lock should not activate at very low (maneuvering) speeds because the electrical signal from the sensors is not strong enough to give the ECU any information.

 

as above

make sure that the front sensors have a good 'earth' connection to the hub

 

want a abs ecu to try? pm me if you do.

 

mine was doing the same thing and it was a wheel sensor

 

Nick i don't understand where the sensor would earth out

Paul

 

are they furred up?

they tend to go open curcit, even more oso if they are stratingt to split around the bolt hole

 

dojj, I cannot see that the earth would be the bolt coller ? i going to cut a broken spare to have a look

And no there not furred up or corroded face of hubs are perfectly clean too

Paul

 

I have a fault with one or more of my ABS sensors and brings the ABS light on intermittanly and pedal pulses sometimes when coming to stop at traffic lights etc.

Whats the best way to check the sensors? Checking the resistance with ohm meter?

What should it be?

 

Right then had a think and a fiddle the sensors are not earthed via the bolt or anything else multimeter showed this to be the case

Also there are no metal to metal joints on the sus to go back to earth all bushed

the only thing i can try now is that the sensors do and can rotate a little once the bolt is loose approx 3mm either side so will have a check of these and report back

James, I've 2 spares ecu's so thanks

Paul

 

Around 1100 ohms mate

 

Cheers

 

Hi,

If it's the same issue you mentioned the other day in another thread did you try what I said and unplug the ABS ECU to test. This is a common problem it will be one of the wheel sensors at fault sometimes they just need a clean if not you will require a new sensor. If you have access to a multi meter there is a way of testing them. I think you measure the resistance, it will defently be explained on here if you do a search.

Kind regards,

Martin.

 

Do you do this on the car and spin the wheel as i have read on other threads of can you just measure the sensor out of the car as i have a spare one i need to check also.

 

as you say paul, it doesn't seem to due to bushes etc. however, the sensor itself has a metal ring where the bolt goes through and the back of that and where it bolts to needs to be clean. sounds like it won't make a difference, but did on 2 of my sierras that had the same problem.

 

Nick that would be due to the "air Gap" then mate i've tested with a multimeter and it don't earth to either connections but if teres any corrosion on the alloy ring that will hold the sensor out enough to fook it up

Paul

 

maybe paul

 

Paul, check that there are not metalic particals magnetsied to any of the parts including the sensor itself.
Particularly in the teeth of the target surface.

 

Forgot to say, I found that tester.

I will be in your area at the weekend if you want to meet up to use it

 

Simon cheers mate pm on the way to ya

Paul

 

They are spot less all 4 of them the only thing is when fitting the 4x4 rears i removed the splash shields which would then make the sensor ring move inboard as the sheild is about 1.5mm thickcan't see that making any difference imo

Paul

 

it's the distance between the sensor pick up and the rings
if you have grease on them it tends to be more problomatic

 

But ford state when fitting sensors smear wheel bearing grease on them before fitting have had grease in mine before and they worked fine

 

too much grease will afect it
especially when you remember that it's bearing grease and it can be thicker than ususal, and it gets dirty
on the rears it's worse as if you get a bit of debris into it when you pull it out it may just think that the cars wheels are permamnently stopped beause you can't see as well as the fronts

 

Fair comment dojj but as said mine are spotless back to the drawing board

Paul

 

Paul,

Put a multimeter on the sensor wires on resistance.
Observe the value the wiggle the wiring vigourously and see if the values change significantly.
Often the sensors fail not because of the sensing head but the wire itself because it gets a pounding from all the
bumps in the road and when the steering is turned.

I had this twice on my sierra and managed to fix them by replcing the cable by cutting of an inch at a time and retesting.
(Carefull of polarity).

Obviously, if you do this, its at your own risk

 

Cheers Si i'm sure its possibly down to air gap will have a go tomorrow and see

Paul

 

Been out again and checked all sensors all clean all read ok with multimeter light stays out even fitted washers were i removed rear splash shields cos i went 4x4 on the back STILL NO JOY!!

could it be that i have very small radius on the front brake flexis??

Any help would be great ta

Paul

 

What was the original problem again?

The Teves Mk 2 on the Sierra has no Keep Alive Memory, so it doesn't remember a thing when it's turned on the next time. As a result, it stores no fault codes - all faults that are indicated are 'live', not old.

Have you done the measurements at the ABS ECU's multiplug? If not, do that - it's all very well a sensor 'checking out', but if the ECU can't see it because of a wiring fault, it might as well not be there.

• Wheel sensors should be anywhere between 800 and 1400 ohms.
• The outlet solenoids in the valve block should register between 2 and 5 ohms.
• The inlet solenoids in the valve block should register between 3 and 7 ohms.
• The mail valve should be between 2 and 5 ohms.

• The fluid level switch (two pin plug on top of the fluid reservoir) can be measured across pins 9 and 10 of the ECU multiplug - this should be a closed circuit when the fluid level is at max, and open when it's higher or lower. If this switch is open, the ABS will be disabled. This was the problem with mine.
• The wheel sensors create a small AC current. At 1 revolution per second, the AC voltage from each sensor should be around 0.2 volts.
• To check the sensors and their cables aren't earthing out, measure the resistance between pin 1 and pins 4, 5, 6 and 7 - should be infinite. The cables are shielded co-axial cable, so if the sheath has worn through, a sensor may be earthing.
• Check the earth connection - meter 11 and 1 for resistance - should be 0 ohms.
• Measure resistance for these pairs to check sensor resistance: 4 & 22, 5 & 23, 6 & 24, 7 & 25. Should be within the tolerance noted above
• To meaure the resistance of the valve block solenoids, measure the resistance between pin 11 (earth) and pins 15, 17 and 35 for the inlets, and between pin 11 and 33, 16 and 34 for the outlets. Tolerances noted above.

Hope some of that helps...

 

Thanks the prob is pulsing pedal at low speeds below 10 mph while coming to a stop

all was fine till i replaced all discs and pads 350 on front and 4x4 on rear and with braided lines aswell

i've heard about the level being incorrect could cause issues but would that not put the light on ?(does when unplugged)

My flexi hoses on the front have a very tight radius could this be an issue?

Paul

 

Only if you had a problem before you changed your discs/pads.

That symptom means that the wheel sensors are feeding false information to the ECU, as below 10mph, there shouldn't be a strong enough signal for the ECU to determine whether or not antilock action is required. It's very unlikely your hoses are to blame because what you're describing is caused by the ECU falsely believing there is a wheel lock situation.

I'd suggest that either one of the sensors is defective, more likely the front, or, there is a poor connection between it and the ECU.