Topic: ABS Light (Read 4657 times)

nixoro · « **on:** 23 July 2006, 11:30:09 »

The ABS light came on last night and keeps coming on when ignition is switched on, can anyone tell what could be causing this and whether there would be any codes in the ecu I could read.

Check light on MID goes out when I press the brakes so the pad sensors work.

The car itself appears to be pulling up ok.

Would this be related in some way to the speed sensors, the speedo seems to be working fine.

Any Suggestions would be most appreciated

Cheers In Advance
Roy

TheBoy · « **Reply #1 on:** 23 July 2006, 12:15:25 »

Likely to be one of the wheel sensors. You'll need a Tech2 to read the ABS stored codes.

summat · « **Reply #2 on:** 23 July 2006, 12:18:55 »

(I really need to take the wheel off mine sometime - mate at work says his '52 plate Veccy has the ABS sensor integrated into the bearing, hence £150 replacement cost. BUT, if that isn't the case....)

Isn't this often caused when you get an accumulation of crud building up on the ABS (HE) sensor, that should sit a few mm away from the slatted disk on each road wheel hub?, maybe worth taking each road wheel off and cleaning up - that'd be the first step anyway. Beyond that and I think you'll need a scope to display the waveform from each wheel sensor to see which one's goosed. (Hmmm, or can this be got from the ECU?, I know it won't be the fuel/emissions train - so e.g. my ODBII reader would be useless)

TheBoy · « **Reply #3 on:** 23 July 2006, 12:23:44 »

Quote

(I really need to take the wheel off mine sometime - mate at work says his '52 plate Veccy has the ABS sensor integrated into the bearing, hence £150 replacement cost. BUT, if that isn't the case....)

Isn't this often caused when you get an accumulation of crud building up on the ABS (HE) sensor, that should sit a few mm away from the slatted disk on each road wheel hub?, maybe worth taking each road wheel off and cleaning up - that'd be the first step anyway. Beyond that and I think you'll need a scope to display the waveform from each wheel sensor to see which one's goosed. (Hmmm, or can this be got from the ECU?, I know it won't be the fuel/emissions train - so e.g. my ODBII reader would be useless)

Yes, clean the wheel sensors, both the actual sensor and the cog bit, and check gap is correct.

The ABS ECU can tell you (what it thinks) is wrong, but you need Tech2 to read this. Also, you can look at live data, but again, Tech2 required.

Worryingly, its not unheard of for it to actually be the ABS ECU itself, esp on post 98 cars

Salty · « **Reply #4 on:** 23 July 2006, 15:26:28 »

I had the same problem on my senator. It was faulty relay with a dry joint, resoldered the joint and it worked a treat(dead lucky)
Omega system may be different though. Cleaning the sensors and rotors like everyone else suggest won't do any harm either.

cipher · « **Reply #5 on:** 23 July 2006, 15:47:19 »

doesnt theboy have a tech2?

nixoro · « **Reply #6 on:** 23 July 2006, 20:25:08 »

Well still have the light issue with any luck it is down to crud build up, had the wheel off this morning on the passenger side rear but couldn't find the speed sensor thinking it was this.

From all the responses it certainly makes sense being one of the brake sensors being dirty, am I right to think its only the front that has these sensors.

Cheers
Roy

Salty · « **Reply #7 on:** 23 July 2006, 20:27:52 »

rears should have them as well

nixoro · « **Reply #8 on:** 23 July 2006, 20:29:47 »

Quote

rears should have them as well

Cheers for the response

Abit concerned now as I didn't see any sensor on the rear when I had the wheel off.

TheBoy · « **Reply #9 on:** 23 July 2006, 20:40:11 »

Fronts are near wheels, rears are each side of diff.

nixoro · « **Reply #10 on:** 23 July 2006, 20:44:45 »

Quote

Fronts are near wheels, rears are each side of diff.

Cheers TheBoy

Having recently been under my car, I found a leak on the rear Driveshaft unit would this be the diff and could well be the source of my problem.

Can anyone confirm my suspitions.

Cheers
Roy

TheBoy · « **Reply #11 on:** 23 July 2006, 20:49:12 »

Possibly - clean it up and see...

nixoro · « **Reply #12 on:** 23 July 2006, 20:51:01 »

Quote

Possibly - clean it up and see...

Shall do, finish early tomorrow so may have some free time.

nixoro · « **Reply #13 on:** 26 July 2006, 07:16:51 »

Finally got around to cleaning the two sensor on the rear still no joy, ABS light still on and I even took car to garage and pressure washed the wheels.

Next move I think is to get the garage to put it on the Tech2 kit to try suss whats going on with it.

Any other suggestions would be most appreciated

Cheers
Roy

Omega VT3000 · « **Reply #14 on:** 26 July 2006, 08:04:30 »

Not sure whether the ABS on Omegas has a memory as such and either needs clearing by Tech 2 or a battery disconnect to extinguish the light?

A common thing, as others have said, on Senators/Calrtons is the surge arrestor relay. Have you hit any debris at any point as the wheel sensors are sensitive to the distance from the sensor pickup (cogged bit)

TheBoy · « **Reply #15 on:** 26 July 2006, 08:33:41 »

Even if fault codes stored in ECU, the light is not on if marked as not present.

Is it a v6, and if so, is the TC light on as well?

Marks DTM Calib · « **Reply #16 on:** 26 July 2006, 08:46:17 »

Plus what is the speedo doing.....

TheBoy · « **Reply #17 on:** 26 July 2006, 08:56:40 »

Quote

Plus what is the speedo doing.....

Original post says speedo appears fine...

Marks DTM Calib · « **Reply #18 on:** 26 July 2006, 09:03:32 »

It points mroe towards the front sensors then.

TheBoy · « **Reply #19 on:** 26 July 2006, 09:05:52 »

Is speed picked up from one of the rear sensors, or combined value from both?

Matchless · « **Reply #20 on:** 26 July 2006, 09:13:47 »

"Check light on MID goes out when I press the brakes so the pad sensors work. "

This only checks the brake light bulbs....a brake pedal switch tells the MID that the lights should be on and the bulb failure monitor checks that they are...if so then the check warning is turned off.

Does the ABS light come on at start-up and remain on or does it only come on once the car is moving? If the first is true then it will be a bad connection, broken sensor or cable, ecu failure etc. If the second then it is a poor quality or no signal from the sensors due to failed sensor, crud in the gap to the toothed ring or corrosion of the toothed ring.

Martin_1962 · « **Reply #21 on:** 26 July 2006, 09:35:22 »

Quote

Is speed picked up from one of the rear sensors, or combined value from both?

Left rear !

nixoro · « **Reply #22 on:** 26 July 2006, 20:57:01 »

Right hopefully I will be able to respond to all posts so far.

ABS light is on constant as soon as I turn the key.
I had the rear of the car up in the air and I removed both rear sensor and cleaned the ends
(coated in crud).
I checked the connections were tight on both rear sensors.
Check light goes out when brake pedal is pressed.
I cleaned both rear cog wheels which the sensor are facing towards when in place.
The speedo is working fine.
2.0 16v with no Traction Control.
I jet washed all the brakes to make sure they were free of crud.

Still to check the front sensors so possible a loose connection.

Hope this helps to make things clearer

Any further suggestions would be most appreciated.

Cheers to all who have posted and made suggestions.
Roy

nixoro · « **Reply #23 on:** 27 July 2006, 17:06:03 »

Going off what I have already said, does anyone think it could be the front sensors.

Not sure how the ABS system works

Am I right to think the check light goes off when the brake lights are tested and the ABS light goes off when the sensors are tested.

Does this makes sense

Cheers
Roy

TheBoy · « **Reply #24 on:** 27 July 2006, 18:29:56 »

Forget the check, thats unrelated.

ABS light comes on with ignition but goes off when diags complete (1 sec or so). So if it doesn't go out, its either failing internal diagnostics (Tech1/2 depending on age would pick it up) or shagged ecu (yes, this ecu can be problematic).

nixoro · « **Reply #25 on:** 27 July 2006, 18:36:40 »

Quote

Forget the check, thats unrelated.

ABS light comes on with ignition but goes off when diags complete (1 sec or so). So if it doesn't go out, its either failing internal diagnostics (Tech1/2 depending on age would pick it up) or shagged ecu (yes, this ecu can be problematic).

Was planning on having a proper look at the front sensors but thunder is not the best to be out in.

Car is going into the grage on Tuesday so will be put on tech2 or equivalent.

Hopefully its just a sensor like the garage think and not a knackered ecu.

Shall clean and check the front sensors properly and see if it sorts itself out.

If not garage should get it sorted if the Ecu is knackered whats the recommended for a 97P 2.0

Cheers in advance
Roy

TheBoy · « **Reply #26 on:** 27 July 2006, 18:52:13 »

Make sure the garage know what they are doing with tech2.

Or, do you fancy a trip to Brackley?

nixoro · « **Reply #27 on:** 27 July 2006, 19:04:03 »

Quote

Make sure the garage know what they are doing with tech2.

Or, do you fancy a trip to Brackley?

They have seen the car before and I seem pretty confident they will have some Idea what is going on.

May take you up on the offer if they dont sort it on Tuesday if thats still ok.

Matchless · « **Reply #28 on:** 28 July 2006, 00:34:03 »

Quote

So if it doesn't go out, its either failing internal diagnostics (Tech1/2 depending on age would pick it up) or shagged ecu.

Or open circuit sensor.
It does a simple continuity check as part of start-up then looks at signal quality / amplitude once car is moving.

TheBoy · « **Reply #29 on:** 28 July 2006, 09:14:00 »

Yup, should have said start up diagnostics, thats what I meant...

TheBoy · « **Reply #30 on:** 30 July 2006, 20:33:57 »

Right them saw the car today, plugged in Tech2, and it came up with ECU error

A quick fiddle with the relays in the ECU fixed the problem, so I cleared the error stored in ECU, took it for a spin whilst doing live data, and it looks good as gold now.

Nixoro - I assume its still OK? BTW, it was a pleasure to finally meet you and your family.

nixoro · « **Reply #31 on:** 01 August 2006, 21:53:02 »

Quote

Right them saw the car today, plugged in Tech2, and it came up with ECU error

A quick fiddle with the relays in the ECU fixed the problem, so I cleared the error stored in ECU, took it for a spin whilst doing live data, and it looks good as gold now.

Nixoro - I assume its still OK? BTW, it was a pleasure to finally meet you and your family.

Big Thanks TheBoy

Sorry for the late respose still limited access at the moment.

It was good to finally get to meet you at last, the drive home was faultless no more ABS light and has'nt been on since touchwood.

I had a go at the cleaning of the relays but they are seriously tight and I could not get them out.

Can anyone tell me if there is a special tool or hidden screw for removal, managed to prise one 3mm but I didn't want to force them in case I broke them.

Again TheBoy a Big Thanks hopefully I can eventually get them out for a good clean.

TheBoy · « **Reply #32 on:** 01 August 2006, 22:13:47 »

I'm really glad that it doesn't appear to be a terminal problem with ECU - probably either a sticky relay or poor contact. It may not even happen again...

It was great to meet you at last - it seems I've known you for ages...

nixoro · « **Reply #33 on:** 01 August 2006, 22:21:49 »

Quote

I'm really glad that it doesn't appear to be a terminal problem with ECU - probably either a sticky relay or poor contact. It may not even happen again...

It was great to meet you at last - it seems I've known you for ages...

I have to admit I wasn't expecting the ECU, what with the garage it was booked in to see thought it was one of the sensors.

Big relief for me, was definately good to finally meet you.

I know what you mean, it seems I've known you for ages.

Markjay · « **Reply #34 on:** 02 August 2006, 09:34:05 »

I can't belive it...

nixoro has an ABS problem, garage say it's a faulty sensor, nixoro posts question here, TheBoy offers his Tech-2 services, problem sorted pronto saving nixoro £££ in garage bills.

Well it's too good to be true! It sounds like adveritising for omegaowners.com! Did it really happen.... I wonder.

There's me and my consipracy theories again... I guess the other option is that this site is really that good and TheBoy is a great guy. :

PS - I've been away so didn't follow this post from the start, had I been around I would have advised nixoro to change the brake light bulbs. Which wouldn't have helped of course. It never does apparently.

TheBoy · « **Reply #35 on:** 02 August 2006, 09:37:27 »

Quote

I can't belive it...

nixoro has an ABS problem, garage say it's a faulty sensor, nixoro posts question here, TheBoy offers his Tech-2 services, problem sorted pronto saving nixoro £££ in garage bills.

Well it's too good to be true! It sounds like adveritising for omegaowners.com! Did it really happen.... I wonder.

There's me and my consipracy theories again... I guess the other option is that this site is really that good and TheBoy is a great guy. :

PS - I've been away so didn't follow this post from the start, had I been around I would have advised nixoro to change the brake light bulbs. Which wouldn't have helped of course. It never does apparently.

I plugged the Tech2 in and thought the worse - it actually said ECU failed (all failed ABS ECUs have always passed diagnostics before). Never seen that before. Fortunately, it looks like we found the cause, and the problem has gone

nixoro · « **Reply #36 on:** 09 August 2006, 11:47:32 »

Quote

Quote
I can't belive it...

nixoro has an ABS problem, garage say it's a faulty sensor, nixoro posts question here, TheBoy offers his Tech-2 services, problem sorted pronto saving nixoro £££ in garage bills.

Well it's too good to be true! It sounds like adveritising for omegaowners.com! Did it really happen.... I wonder.

There's me and my consipracy theories again... I guess the other option is that this site is really that good and TheBoy is a great guy. :

PS - I've been away so didn't follow this post from the start, had I been around I would have advised nixoro to change the brake light bulbs. Which wouldn't have helped of course. It never does apparently.

I plugged the Tech2 in and thought the worse - it actually said ECU failed (all failed ABS ECUs have always passed diagnostics before). Never seen that before. Fortunately, it looks like we found the cause, and the problem has gone

Yep problem sorted ever since seeing TheBoy the other weekend, the car has not had the dreaded ABS light come back fingers crossed it never will, TheBoy is a top bloke and I can vouch for that.

Granted I still haven't managed to get the relays out for cleaning, but atleast I know where to look first if it ever decides to return, hoping not.

Big Thanks TheBoy

TheBoy · « **Reply #37 on:** 09 August 2006, 12:08:55 »

ahhh, I'm touched.... [smiley=2vrolijk_08.gif]

News:

Author Topic: ABS Light (Read 4657 times)

Martin_1962