Pre-Cat Oxygen sensor?

[ard]

These days the BMWs do odd stuff with voltage regulation and charging..I believe the voltage is allowed to drop too low after starting but during operation and this can throw off odd errors from some modules. just weird random modules with faults. You wont notice running issues but the stuff hanging on the bus will not be happy.

Just wag.

[bawareca]

Originally Posted by ard

These days the BMWs do odd stuff with voltage regulation and charging..I believe the voltage is allowed to drop too low after starting but during operation and this can throw off odd errors from some modules. just weird random modules with faults. You wont notice running issues but the stuff hanging on the bus will not be happy.

Just wag.

Absolutely!It is probably just a random code.
As a matter of fact the computer is monitoring the voltage of the battery and the current that is drawn and if the voltage drops too quickly it will throw a code and warning light.It may not come back for a long time.I have had some stored in my car's memory,but the car will start after being parked for 2 weeks.

[ard]

Originally Posted by bawareca

Absolutely!It is probably just a random code.
As a matter of fact the computer is monitoring the voltage of the battery and the current that is drawn and if the voltage drops too quickly it will throw a code and warning light.It may not come back for a long time.I have had some stored in my car's memory,but the car will start after being parked for 2 weeks.

Question:

Will it show the 'workshop service' warning? Like this:



but not a CEL??? (Which is the classic 'yellow engine symbol')