Sbc failure again!?!

karozza

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Has anyone got experience with this?

March this year, went for a 4 day road trip to Sicily & at one point got SBC failure "Reduced Braking" alerts in red. Oh & hardly any brakes! After about an hour, all back to normal & drove back to Malta, no issues.

Had it checked on STAR at an Independant garage & MB, SBC not EXPIRED & replaced brake fluid. All good. Even went on holiday again to Sicily with no SBC issues. Independent garage stated rear pressure regulator fault & MB stated front driver's regulator fault-but the latter was surely only because there was a bleed valve leaking hydraulic after the brake fluid replacement; I noticed the leak after taking the car from MB.

This morning started car in the garage to give the car a wash, again, same SBC warnings. Washed the car around 2 hours, started car & all good again!

Could it be the SBC defective but would it come back to life for so long!?
 

Auto-mobile

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So your sbc failed and you had nothing replaced? I'm not suprised it's happened again, you must have a underlying issue, there would have been codes after the first failure.
 
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karozza

karozza

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Auto-mobile said:
So your sbc failed and you had nothing replaced? I'm not suprised it's happened again, you must have a underlying issue, there would have been codes after the first failure.


Only replaced the brake fluid as when on STAR at the Indy, that's what it recommended first & if not successful, replace SBC. The codes referred to what I explained above regarding faulty regulator.

I'm puzzled why it took so long to show any failure & this is my query!? Shouldn't an SBC failure stay defective or could it be something else?
 

Auto-mobile

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Needs the codes re read again, may be the sbc unit this time if the display is in red.
 

cb1965

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So the first time you had it you had no brakes at one point and yet all that was done afterwards was to replace the brake fluid and you have been driving it ever since.... er.... that is not logical!

Replace the SBC unit would be my option as they are a know weakness (amongst many) with these cars!

May seem drastic, but better than the alternative!
 
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karozza

karozza

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cb1965 said:
So the first time you had it you had no brakes at one point and yet all that was done afterwards was to replace the brake fluid and you have been driving it ever since.... er.... that is not logical! Replace the SBC unit would be my option as they are a know weakness (amongst many) with these cars! May seem drastic, but better than the alternative!

Don't really understand your point!? Replacing a part, costing €2200 here, without being sure the part is at fault sounds illogical to me! This is why I asked on here if anyone has had a similar experience. Or, if anyone can actually confirm the SBC is faulty after such an experience.

STAR diagnostic actually recommends replacing the brake fluid first. I have also read on forums similar experiences caused by a faulty convenience battery. Also read that it is very unlikely an SBC faulty when this happened at around 26000 miles, now at 28000 miles. I could be unlucky & have a prematurely defective SBC!? I have not learnt the SBC to be a weakness, but they do expire after a certain number of pulses, which mine has not.

Been running around all day with no issues. To my knowledge, unless someone may explain otherwise, when an SBC fails, it keeps on failing regularly.

If need be, I will replace the SBC, just don't want to go through the expense & find out something else is the problem.
 

flango

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Just buy the SBC unit from Germany and get an indie to fit it search my other posts for details it's just over £600 with a 1.42 € exchange rate

Alternative extend the service life counter using STAR
 
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karozza

karozza

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flango said:
Just buy the SBC unit from Germany and get an indie to fit it search my other posts for details it's just over £600 with a 1.42 € exchange rate Alternative extend the service life counter using STAR

I did check on extending the service & MB said this is not always successful; they also stated the fault shown has nothing to do with the service life counter.

Have checked with Germany & when I gave them my part number, they said they don't do mine.

Might try to call them tomorrow. Also, going to check with BBA in the UK.
 
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karozza

karozza

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So far been running around with no SBC failure........very strange

Next step, will take it on STAR & check history, although, this will take some time now as I will be abroad all of the coming week & the Indy will most probably shutdown over the holidays!

Having checked around the SBC, seems there's a slight dampness(feels like a fluid) on the main harness coming from the SBC main electric plug further down the bend & where it rest on the inner panel.....very strange indeed

At least, now Germany have confirmed they have a new Bosch SBC that matches my part number. They do not post to Malta, so checking out alternative postage.

As it seems that no-one has posted any experience of a failure alert with the SBC coming back to life(that has not expired) for long periods, I will post further & share what I learn.
 

OneForTheRoad

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The only thing I can think offis the fluid level dropping from a leak somewhere. Are you checking the level at all ???
 

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