New Twist (for me anyway) on Battery Reset

[ENZ525]

Just seen this on ML...

""Found a solution (per a Maserati mechanic). Disconnect both battery cables. Touch them together, which shorts out the capacitors, etc (I know, scary, huh?)
This does a hard hard reset. Plug everything back in, start the car, then do the radio code. Everything works like a charm.
Hope this can help someone else down the road."

It is a solution posted by a guy whose stereo started playing up after the battery went dead on his QP.

I have never heard of such a thing...any body care to comment?

Regards,
Enzo.

 

[lozcb]

Just seen this on ML...

""Found a solution (per a Maserati mechanic). Disconnect both battery cables. Touch them together, which shorts out the capacitors, etc (I know, scary, huh?)
This does a hard hard reset. Plug everything back in, start the car, then do the radio code. Everything works like a charm.
Hope this can help someone else down the road."

It is a solution posted by a guy whose stereo started playing up after the battery went dead on his QP.

I have never heard of such a thing...any body care to comment?

Regards,
Enzo.

Me and wires aren't a good mix , i'd rather ring Roberto or Myles and check first rather than take it on a forum quote /unquote
wouldn't want to wipe an ecu or two


regards loz

 

[ENZ525]

Hi Loz,
Just sounded bizarre to me...
I would not want to try this, but it sounds like this guy did and it worked...
Regards,
Enzo.

 

[conaero]

Hi Loz,
Just sounded bizarre to me...
I would not want to try this, but it sounds like this guy did and it worked...
Regards,
Enzo.

More luck than judgement, not worth the risk in my honest opinion.

 

[Emtee]

At the outset I should say that I'm no sparky, however this doesn't sound like a 'short' to me as there's no power involved since both leads have been removed from the power source. With that said I can't therefore see what this would do other than perhaps drain any residual charge in the capacitors? This might lead to the description of a 'hard' reset whereby you're actively neutralising any remaining charge or static build-up?

Do not take my word for this however, it needs clarification from someone much more knowledgeable than me.

 

[bumoleo]

I guess the engine management system stores the erros/warning codes (airbag etc) in some kind of non volatile RAM. This can't be battery backed up otherwise we'd all have to replacing some
small batteries in the controllers every 7 years or so therefore i assume its nvSRAM. I can't imagine that by shorting the battery terminals that this memory would then be erased. If this memory
was stored by charge in a capicitor then it would mean that by leaving the battery disconnected for a long time the charge in the capicitors would leak away and eventually the stored values would be lost.

Does anybody have anymore details about how, for example the airbag warning light comes on after a flat battery. Does this happen everytime the battery terminals are disconnected
or only when the battery discharges slowly?

My guess would be that its only when the battery goes flat, probably disconnectiong the battery and reconnecting does not make the warning lights come on?
This would indicate to mean that as the voltage on the airbag sensors goes down(battery losing charge) that it gets to a threshold and writes to the memory that the airbag exoploded
or whatever. This is stored in the nvSRAM and when the battery is recharged it is flagged as an airbag error.