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RiccardoG

ABS / brake lights "trifecta"

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HI All,

 

Yesterday was a hot day and after ~45min of London traffic with the a/c on I felt a slight tap from the brake pedal and immediately after the 3x lights (brake / abs and...?) on the dash cluster lit up in orange. Rest of car seems to drive ok. Speedo ok, I think gears all ok (as in, not in failsafe mode), didn't check cruise.  Car must have been hot as the viscous fan came on just before the lights lit up, it normally never does. I know this can trigger the ABS module fault.

 

I'm assuming this to be the well knows ABS module issue and am inclined to just whip it off and send to be rebuilt. It's not ABS sensors for sure as a) they're relatively recent and b) it was dry. (I had the issue with them a few years ago and since solved.)

 

Any other thoughts, or should I just go ahead as planned?

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Also, any suggestions where to send it to? I was all set to use Actronics but when I called just now they were super unhelpful as I'm not "trade"...

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25 minutes ago, RiccardoG said:

HI All,

 

Yesterday was a hot day and after ~45min of London traffic with the a/c on I felt a slight tap from the brake pedal and immediately after the 3x lights (brake / abs and...?) on the dash cluster lit up in orange. Rest of car seems to drive ok. Speedo ok, I think gears all ok (as in, not in failsafe mode), didn't check cruise.  Car must have been hot as the viscous fan came on just before the lights lit up, it normally never does. I know this can trigger the ABS module fault.

 

I'm assuming this to be the well knows ABS module issue and am inclined to just whip it off and send to be rebuilt. It's not ABS sensors for sure as a) they're relatively recent and b) it was dry. (I had the issue with them a few years ago and since solved.)

 

Any other thoughts, or should I just go ahead as planned?

 

I've had this on my touring; turned out that all 4 sensors were really gunked up. So all 4 removed, cleaned and the connections cleaned also; never any issues since. I know you say yours are fairly new; but well worth checking again; always good to have a free fix :) 

 

But with mine being a Jap import; the sensors were easy to remove as there's no corrosion; I know it can be completely the opposite on a UK car; worth bearing in mind!

 

I'd also have the car off; undo the ABS pump plug, give that a decent clean with contact cleaner. Let that dry, reconnect and then start the car; see if that makes any difference

 

Other than that; it obviously could be a failed module & the only company I really know of is BBA Raman

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I had a similar issue, tried cleaning/replacing sensors etc and made no difference. I sent the module off to someone on eBay Leon-repairs.

 

great service and honesty, I sent two incase the original didn’t repair but he was confident and correct that my original could repair.

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Thanks for the replies Dan and Pete. Not so easy for me to check the sensors as it involves jacking the car up, which I can't do.

 

I removed the module and sent it to BBB Reman as they seem to come well recommended and also offer a lifetime guarantee on their repairs. Lets see how it goes, will keep you posted.

 

 

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How easy are abs sensors to get to?

 

I got the three lights today and a “pump fault”

 

i did drive through a couple of large puddles and wonder if I upset something.

 

I've reset lights for now and will see if anything re-occurs

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2 hours ago, AdamB said:

How easy are abs sensors to get to?

 

I got the three lights today and a “pump fault”

 

i did drive through a couple of large puddles and wonder if I upset something.

 

I've reset lights for now and will see if anything re-occurs

 

Sensors access is easy; wheel off and it's there (as is the connection); but... The UK sensors apparently are hard to remove as their small hex bolt corrodes and seizes, so it may be worth soaking them in WD40 first to see if that helps; or even better, Wurth Rost Off Ice

 

Cheap to replace also

 

Heat can cause ABS lights as can a filthy connector plug in the engine bay; give that a good clean and see how you go. Start cheap/easy and go from there etc :) 

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Thanks

 

anyone know if there’s a good way to test / diagnose the various components.

 

most people are pointing towards the control unit, as this can cause a multitude of errors.

 

ive also been told the module is in two different places… one says it’s the black but attached to the pump in the engine bay, another says it’s behind the glove box?

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43 minutes ago, AdamB said:

Thanks

 

anyone know if there’s a good way to test / diagnose the various components.

 

most people are pointing towards the control unit, as this can cause a multitude of errors.

 

ive also been told the module is in two different places… one says it’s the black but attached to the pump in the engine bay, another says it’s behind the glove box?

It depends on the age of the car, i think post 1999, its in the engine bay, prior to that is under the glove box

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Yes later cars have the module under the bonnet next to the engine and they suffer from the heat built up there. When I replaced mine I fabricated a heat shield for the unit but I doubt that it makes a great difference. Certainly try the simple things first but often a failing module generates a false error code such as a wheel sensor. Sadly the trifecta often leads one through a series of false hopes before you have to bite the bullet and have the module repaired. I was able to get a new unit from Germany a few years ago but the price has since shot up enormously and a repaired unit makes a lot of sense.

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Unbelievable coincidence, just got this fault!!  It comes on, goes off, comes on goes off and then comes and stays on until I switch the ignition off and then seems ok for a few miles and then the cycle repeats. No errors on Carly so waiting for Jimmy’s software to download and plug INPA in and see what that says. Will have my own tale to add to this thread. Interestingly had a dead battery last week so wondering if I’ve upset the system somewhere either with the dud unit or installing the new one. It’s warm so that is probably another option and I’ve got the 6 cylinder which has the heat shielding already!  

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Behind the glovebox modules IIRC are up to 7/96

My car would throw codes every now and then in the summer... especially on heavy stop/go traffic with A/C on as you mention. Did you let it cool properly, overnight, and checked again? 

 

as for the fellow E39er reporting "pump" fault, it's the code just "pump" or "pump solenoid" or something?

 

Also worth mentioning that Dan's suggestions are very very good and most people overlook that. Sometimes you just don't have an idea how gunked up the phonic wheel is inside the hub assembly... a good blast with brake cleaner while spinning the hub with the sensor off sometimes cures more than just go willy nilly replacing stuff. Also worth checking, at this age of our cars, the body side connector of the wheel sensors and the little cage that holds them tight, and clean everything and use dielectric grease on every contactor you undo and clean.

Edited by jicaino

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6 hours ago, jicaino said:

Behind the glovebox modules IIRC are up to 7/96

My car would throw codes every now and then in the summer... especially on heavy stop/go traffic with A/C on as you mention. Did you let it cool properly, overnight, and checked again? 

 

as for the fellow E39er reporting "pump" fault, it's the code just "pump" or "pump solenoid" or something?

 

Also worth mentioning that Dan's suggestions are very very good and most people overlook that. Sometimes you just don't have an idea how gunked up the phonic wheel is inside the hub assembly... a good blast with brake cleaner while spinning the hub with the sensor off sometimes cures more than just go willy nilly replacing stuff. Also worth checking, at this age of our cars, the body side connector of the wheel sensors and the little cage that holds them tight, and clean everything and use dielectric grease on every contactor you undo and clean.

C73D4EB7-8541-4514-B43E-4A4228ACF1AD.jpeg.08ae55dd3e5be4ff90157e0b75cb66d4.jpeg

 

not had a chance to drive it again yet

 

ill try and have all the sensors off/out and check connections etc.

 

luckily I work in the electricity industry, so have access to some reasonable solvent cleaners, de-watering sprays and contact greases.

 

ive also emailed BBA reman to enquire about their module repairs.

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Guys, my personal experience on this through the years has been:

- Water (rain, washing) impacts ABS sensors in the wheels. In my case the fault generally went away when the car dried up;

- Heat impacts the control module (in the engine bay on my facelift car). In my case once that "went" it stayed broken and the fault could not be reset. The diagnostics pointed to the rear pax sensor but that is a red herring as I understand its where the circuit starts

 

The above might or not be what you experience!

 

Some other notes

- Removing ABS sensors can be difficult indeed. Careful with them, HR Owen BMW eventually broke my rear wheel bearing and an ABS sensor replacement turned to a £400+ job (granted that was at main dealer)

- Removing the ABS control unit in the engine bay was very easy. Getting it re-manufactured costs ~£250 all in, so its not that bad a deal. BBB reman also gives you a lifetime warranty on it

- Faulty wiring might also play a role in some cases, I think this would be difficult to diagnose

 

Good luck in sorting it!

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So I’ve not checked the sensors yet, but I’ve got a quote so will most likely just replace front sensors for now. Going through puddles defo seems to increase frequency of the lights, however it did it again in the dry yesterday, so it could well be the module still at fault.

 

I've heard mixed reviews of BBA and they haven’t yet replied to my queries.

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On 27/07/2021 at 08:08, AdamB said:

C73D4EB7-8541-4514-B43E-4A4228ACF1AD.jpeg.08ae55dd3e5be4ff90157e0b75cb66d4.jpeg

 

not had a chance to drive it again yet

 

ill try and have all the sensors off/out and check connections etc.

 

luckily I work in the electricity industry, so have access to some reasonable solvent cleaners, de-watering sprays and contact greases.

 

ive also emailed BBA reman to enquire about their module repairs.

From this German diagnostic it looks like a return pump failure and steering angle sensor. My bet is nothing to do with sensors either module or pump.  Only my view though as i have a parallel thread going on with my own problems.

 

Unless i missed it there's no mention of speed sensors. Could be wrong.

 

If that is the case there are a few on ebay with entire pump and module.  Maybe change the module first and see what happens if going down that route.

 

 

 

As an update.  In my case if I hadn't found a new old stock module I would personally have tried to find a way of getting it done by ACtronics and if that were not possible (see other post) then by ECU testing Automotive ECU Testing - ECU Repair and Exchange.

Edited by Dbcrd
Update

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The pre-charge pump error usually points to the failed DSC module. Had it twice and in both cases (two cars) the DSC had failed. One fixed by a competetent electrician, another destroyed by a butcher so I had to buy a new one off ebay.de. And had it coded to the car. 

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Have you tested the ABS pump - either via INPA or directly 12V on the connector?

It may well be that the pump has failed, being 20 odd years old - it's on the hydraulic valve block. You can also connect 12V directly and see if you can hear it running.

The error has nothing to do with ABS sensors. 

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I'd do the data buses diagnose. That's unplugging the modules one at a time to see if there's one faulty module that's sending noise over the data lines so the modules fail to communicate. 

After discarding data bus noise due to a faulty ecu somewhere, I'd print the pinout for the wires at the DSC connector and check the physical wiring. 

On the off chance that you've got a 540i built post 9/98 (vanos) if you have the water cooled alternator, your VR could be on the way out allowing occasional high voltage peaks that can send the buses on fire too and cause modules to halt communications protocol, giving place to weird errors. 

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22 hours ago, dmarkovina1 said:

Have you tested the ABS pump - either via INPA or directly 12V on the connector?

It may well be that the pump has failed, being 20 odd years old - it's on the hydraulic valve block. You can also connect 12V directly and see if you can hear it running.

The error has nothing to do with ABS sensors. 

If I reset the lights once engine cooled, the abs works, I can go and stamp on the brakes etc and get the correct response.

 

this only happens when the heat soak occurs

 

all irrelevant now though dhl dropped the parcel :(

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41 minutes ago, AdamB said:

If I reset the lights once engine cooled, the abs works, I can go and stamp on the brakes etc and get the correct response.

 

this only happens when the heat soak occurs

 

all irrelevant now though dhl dropped the parcel :(

 

That's exactly what mine was doing...

 

No lights when the car was cold; stood overnight etc

 

But as soon as the engine was up to temp; the lights came on

 

Sent the module off to ECU Testing; they tested, confirmed the issue and rebuilt it and it was perfect after that; sods law it happened a week before selling the touring!

 

What about getting the same module off eBay or if someone can lend you theirs for a few days and see if that has the same issues; least that way you know then

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If this only happens when very hot than you need either fixing yours or getting a new DSC unit. My understanding was that it happened first when hot and that issue has persisted since then hence the ABS pump troubleshooting suggestion - as the error persisted. If you are getting a new or buying someone else's used (only if cheap) then it has to be coded to your car. When you clear the errors do both appear immediately, even when cold? The thing is that you also have steering wheel sensor issue which would also trip off the ABS lights - if memory serves me...

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