How does the BMW counting system work?

[andysat]

Hi all,still in limbo with my emission light problem(sorry for going on and on about it),but when i rang the second indy for another opinion,he said the emission light comes on because of the BMW counting system,i suspect it counts the fault until it maxes out then the light comes on?
Does this sound correct?
Will it still count the fault now i am town driving (even tho it only comes on when giving it the beans)?
Thanks.

 

[Stuart Truman]

BMW Counting system? Never heard of that before. Maybe they mean how BMW counts all the money from abortive dealer visits.

"I say Mr Schmidt, we've not counted enough money this week. Turn on a few fault lights will you?"

 

[mrlozzer]

BMW Counting system? Never heard of that before. Maybe they mean how BMW counts all the money from abortive dealer visits.

"I say Mr Schmidt, we've not counted enough money this week. Turn on a few fault lights will you?"

 

[andysat]

-he said when the light is triggered it comes on only after the fault count has reached its limit.I thought it read a fault then put the light on.

 

[Lillywhite]

In the words of the Singing Postman - 'They think we are simple, they think we are slow, so take my advice boy, and watch how you go'. :wink:

 

[cj_eds]

Its not a BMW thing, it's an industry standard thing. For every fault and diagnostic test ran by the ECU's they log the errors. When the same tests pass without noting a fail, it also logs the passes. When designing the diagnostics for a car it's someone's job to decide for every error how many times it's allowed to occur, what the consequences are (a fault code, MIL light, limp home mode etc) and finally whether it's allowed to 'heal' itself (whether sufficient test passes clear the fault or not).

 

[andysat]

Are you saying they were b/s ing me?

 

[projoy]

Hi andysat
My emission light came on after or during motor way driving and turned out to be a coil pack braking down replaced with new all ok

 

[cj_eds]

PS... With regards to your emissions light, it depends on how the BMW engineers decided it should work as to whether it's still counting or not. Some diagnostic tests run all the time, others have criteria before you can run the test.

 

[andysat]

Its not a BMW thing, it's an industry standard thing. For every fault and diagnostic test ran by the ECU's they log the errors. When the same tests pass without noting a fail, it also logs the passes. When designing the diagnostics for a car it's someone's job to decide for every error how many times it's allowed to occur, what the consequences are (a fault code, MIL light, limp home mode etc) and finally whether it's allowed to 'heal' itself (whether sufficient test passes clear the fault or not).

Aahh ok

 

[andysat]

PS... With regards to your emissions light, it depends on how the BMW engineers decided it should work as to whether it's still counting or not. Some diagnostic tests run all the time, others have criteria before you can run the test.

Thanks again!

 

[andysat]

Hi andysat
My emission light came on after or during motor way driving and turned out to be a coil pack braking down replaced with new all ok

Thanks for the input mate,did your zed drive any different straight away when the light came on?

 

[projoy]

At first it drove OK the light came on and if i restarted the car it went out but then the light came on and did not go out and run as ruff as a dog
The BMW specialist said the coil pack start to break down under hard driving conditions before going all together

 

[andysat]

Okay thanks mate,my zed runs no different with the light on or off-thats whats so annoying!

 

[bcworkz]

I found the following explanation in a training manual, but there were several conditions where
this does not apply (not sure what constitutes a customer driving cycle either):

1. A fault code is stored within the ECM upon the first occurrence of a fault in the system
being checked.
2. The "Malfunction Indicator Light” will not be illuminated until the completion of the sec-
ond consecutive "customer driving cycle" where the previously faulted system is again
monitored and a fault is still present or a catalyst damaging fault has occurred.
3. If the second drive cycle was not complete and the specific function was not checked
as shown in the example, the ECM counts the third drive cycle as the “next consecu-
tive“ drive cycle. The "Malfunction Indicator Light” is illuminated if the function is checked
and the fault is still present.
4. If there is an intermittent fault present and does not cause a fault to be set through mul-
tiple drive cycles, two complete consecutive drive cycles with the fault present are
required for the "Malfunction Indicator Light” to be illuminated.
5. Once the "Malfunction Indicator Light” is illuminated it will remain illuminated unless the
specific function has been checked without fault through three complete consecutive
drive cycles.
6. The fault code will also be cleared from memory automatically if the specific function is
checked through 40 consecutive drive cycles without the fault being detected or with the
use of either the DISplus, GT1 or Scan tool.

 

[andysat]

Thanks mate-that was in depth!

 

[Paradroid]

I had a Hyundai Coupe years ago (the V6 model) and on a service they said it had logged loads of errors about one of the cylinders due to a knackered spark plug. This was a bit of a surprise as I'd never seen any warning light. So it's definitely true that errors can be logged and only flagged up when seen as serious.

 

[andysat]

Must admit i like the Hyundai coupes

 

[Stuart Truman]

I reckon the fault light comes on with the following conditions:

1) is the car out of warranty
2) does the driver have any disposable income

Either are enough to trip the indicator


Tapatalking...

 

[andysat]

I reckon the fault light comes on with the following conditions:

1) is the car out of warranty
2) does the driver have any disposable income

Either are enough to trip the indicator


Tapatalking...

:lol: