Emergency Brake Assist Failure

Emergency Brake Assist Failure

Author
Discussion

Ken Figenus

3,833 posts

49 months

Friday 29th December 2017
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I haven't received it yet mate but I think Steve (Aston 1936) discovered he could read more codes and get deepetr access if he told his generic OBDII device that the car was a Ford ( https://aston1936.com/2016/04/12/getting-more-from... ). He then discovered this Foxwell device came with the unique AM codes. Steve deserves a big warm British beer biggrin

bogie

13,428 posts

204 months

Friday 29th December 2017
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PrAston said:
I'm getting a triumvirate of error messages on my 05 DB9: Emergency Brake Assist Failure, DSC Service Required, and Traction Control Temporarily Off. It seems to be a genuine failure, i.e., shutting off and restarting doesn't clear it. It appeared after the car had been sitting for about two weeks, and I had never had the warning come up before.

From what I've read it sounds like the Brake Pressure Transducer is the most likely culprit. I know it can be other things, but my code reader won't talk to the ABS module, so I don't have any way of narrowing it down. Should I replace it on a hunch? If it's faulty and I replace it, will the message go away on its own or does it have to be cleared manually? It doesn't look like bleeding the brakes is required, but if it is, can that even be done the conventional way? I ask because the manual talks of hooking up to AMDS which manipulates the ABS pump to bleed the brakes.

Any other tests that can be done or general suggestions? Trying to avoid a 250-mile trip to the dealer.
the transducer is likely and cheap/quick enough just to try a fix. It will clear itself after a couple of stop/start cycles....at least mine did

I didnt need to bleed the brakes as didnt lose hardly any fluid, it really was just a trickle if you are quick. Check brake fluid level after and top up a little if needed.

Rappa

469 posts

202 months

Friday 29th December 2017
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Ken,

Many thanks. Ford software it is then, please let us know how it goes when you get it.

Sean

Edited by Rappa on Saturday 30th December 01:47

Ken Figenus

3,833 posts

49 months

Saturday 30th December 2017
quotequote all
Rappa said:
Ken,

Many thanks. Ford software it is then, please let us know how it goes when you get it.

Sean

Edited by Rappa on Saturday 30th December 01:47
I will - although my 'childlocks' error has reset itself by now! I imagine the software/error codes are quite bespoke to Aston by now hence needing the Aston OBDii version but looks like you get further telling a generic reader to reference Ford error codes (on V12's - prob not V8's as there is some Jag heritage there).

PrAston

4 posts

12 months

Wednesday 7th February
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I replaced the transducer (no bleeding required thank god), and have driven the car through at least 6 or 7 stop/start cycles, but the message has yet to clear. How long should I give it before I start looking into other possibilities?
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davek_964

Original Poster:

4,804 posts

107 months

Wednesday 7th February
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PrAston said:
I replaced the transducer (no bleeding required thank god), and have driven the car through at least 6 or 7 stop/start cycles, but the message has yet to clear. How long should I give it before I start looking into other possibilities?
You should already be looking. Mine cleared each time I stopped / started the car and only came back when braking.
Is yours permanently on? If so, that seems odd.

Mine was the brake pedal travel sensor - but as I say it cleared when I turned the car off and only came on again when braking.

PrAston

4 posts

12 months

Tuesday 12th June
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I finally admitted defeat (after trying a new transducer, new battery, and everything I could do with a Foxwell NT510) and took it to the dealer. Tech says all the relevant sensors are reporting normally, which means its the ABS module, to the tune of $3800. The part is about $2800 of that, the labor is about 4.5 hours @ $175, the rest is fluid, tax, etc.

The tech has an inquiry into the factory to see if there are any other possibilities, but no word on that so far. Is the ABS module a likely culprit? And is $2800 a legitimate price for it? I've located a used one for $819, but obviously there is some risk there, even at a saving of $2000.

davek_964

Original Poster:

4,804 posts

107 months

Wednesday 13th June
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If the car is showing the warning, surely it's logged a fault which tells them why?

sundayjumper

498 posts

214 months

Wednesday 13th June
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davek_964 said:
If the car is showing the warning, surely it's logged a fault which tells them why?
Depends.... the car will log some errors, but it may take some investigation / experience / luck to find the actual fault.

Example: my old BMW once threw up an engine warning, and on reading the codes it said there was a fault with injector 1, injector 2, injector 3 & injector 4. Four new injectors from BMW are a lot of £££s.

But if I had replaced all four injectors that wouldn't have fixed it, because the actual problem was that the wiring to *one* injector had come loose, rubbed against the fuel rail and was shorting out. Actual repair cost - some of my time, and a couple of inches of insulating tape.

Beware of "computer says...." !!


davek_964

Original Poster:

4,804 posts

107 months

Wednesday 13th June
quotequote all
sundayjumper said:
davek_964 said:
If the car is showing the warning, surely it's logged a fault which tells them why?
Depends.... the car will log some errors, but it may take some investigation / experience / luck to find the actual fault.

Example: my old BMW once threw up an engine warning, and on reading the codes it said there was a fault with injector 1, injector 2, injector 3 & injector 4. Four new injectors from BMW are a lot of £££s.

But if I had replaced all four injectors that wouldn't have fixed it, because the actual problem was that the wiring to *one* injector had come loose, rubbed against the fuel rail and was shorting out. Actual repair cost - some of my time, and a couple of inches of insulating tape.

Beware of "computer says...." !!
Absolutely - but I'd want any faults fully investigated before spending that kind of cash on an ABS module!

yvr

258 posts

78 months

Wednesday 13th June
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I don't know if the DB9 ABS unit is sourced from Jag, but XK8s suffered from broken solder joints inside the ABS module which resulted in similar dash warnings. Lots of info if you google, and a DIY repair.

PrAston

4 posts

12 months

Thursday 14th June
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I actually had an XK8 that was throwing similar codes, but I sold it before I really investigated it properly. It does seem to be a common problem with XK8s, and although the DB9 uses a similar looking Ate unit, I can't find any reference to a comparable failure in a DB9.

The dealership apparently heard back from the factory and believe it is indeed the ABS module. Whether I go with a new or used module, or repair the old one, is there any part of the job that would be dealer-only? I ask because I can only assume the dealership would refuse to install a used or reconditioned part, and if an AMDS unit is required to bleed the system or reset codes, that results in the potentially awkward situation where I have to ask the dealership to finish a job they didn't start, not to mention the time and hassle of moving the thing back and forth around the state.

Incidentally, the price of a new module averages around $1300 from several sources, so the dealer would seem to be doubling the price.