Help: determine real mileage

[cbg-host]

Hi guys
I inspected a z4 today with my mechanic. We found the odometer reading was tampered because of below findings

Basically the current instrument odometer reading is less than last DSC warning mileage reading.

I am wondering is any place or ecu to read the current real mileage? Thank you.

 

[AnubisZed]

Potentially the DSC may have been changed for a used one from a higher mileage car!

If the cluster (KOMBI) was changed, for a used set, then you'd have a red dot at the end of the displayed mileage on the clocks. But if it had then been viginised (removal of previous mileage and VIN) it would now pick up the original mileage from the CAS module, as the mileage is stored in the KOMBI and CAS at the same time. The coder would then write the correct VIN to the replacement KOMBI.
So if that was the case then the mileage that the DSC is reporting would be incorrect with the CAS, if you see what I mean?

 

[cbg-host]

But if it had then been viginised (removal of previous mileage and VIN) it would now pick up the original mileage from the CAS module, as the mileage is stored in the KOMBI and CAS at the same time.

Thanks for your reply. I guess a followup question is that any chance KOMBI & CAS both get replaced and coded to tamper the mileage? Or it is technically feasible but too much effort and not worth it? Thanks again.
Also if I bring my ISTA, I could read the mileage from CAS? Unfortunately i didn't bring my laptop.

 

[Pondrew]

Unfortunately i didn't bring my laptop.

Oh no....you didn't bring your laptop to view a car you want to buy?
What the hell is wrong with you?
It's 2025; schoolboy error right there. :roll:

Sarcasm isn't available on ISTA BTW (or maybe it is). :?

 

[cbg-host]

Oh no....you didn't bring your laptop to view a car you want to buy?

I brought my mechanic. Was thinking the scanner would do the same trick...

 

[Pondrew]

I brought my mechanic.

This mechanic you 'own'; is he/she allowed in the house?
Asking for a friend.

 

[AnubisZed]

But if it had then been viginised (removal of previous mileage and VIN) it would now pick up the original mileage from the CAS module, as the mileage is stored in the KOMBI and CAS at the same time.

Thanks for your reply. I guess a followup question is that any chance KOMBI & CAS both get replaced and coded to tamper the mileage? Or it is technically feasible but too much effort and not worth it? Thanks again.
Also if I bring my ISTA, I could read the mileage from CAS? Unfortunately i didn't bring my laptop.

The chances of that are very slim, but not impossible
The chances of the DSC being changed are a hell of a lot higher though.
Saying that, I'm not aware of the DSC having the milage stored in it, like I say it's only stored in KOMBI and CAS.
Having to replace both the CAS and KOMBI at the same time is extremely slim, replacing them at different times would make more sense, and in doing so they'd get the correct mileage from the other unit, NOT the DSC.

So in conclusion, I'd say the milage of that Z4 is 72137 kilometres (44823 miles)

 

[cbg-host]

Saying that, I'm not aware of the DSC having the milage stored in it, like I say it's only stored in KOMBI and CAS.

It might be reading mileage from KOMBI or CAS when the tyre warning happens? Not sure just wild guessing. If anyone knows how it works, please shade some lights.
I really liked the z4. No oil leake, engine runs smooth, drive smoothly, no suspension noise and etc..
Almost bought it before finding this issue..

 

[AnubisZed]

It might be reading mileage from KOMBI or CAS when the tyre warning happens? Not sure just wild guessing. If anyone knows how it works, please shade some lights...

What? :? Tyre warning?

The tyre warning comes via one of two ways;
FTM, Flat Tyre Monitor. As air leaks, tyre pressure decreases, and the tyre rotates faster. ABS sensors on the wheels detect a change in wheel rotation speeds, which signifies a change in the roll radius, or pressure level, of the tyres.
TPMS, Tyre Pressure Monitoring System. This system relies on dedicated sensors that sit inside the tyre valves and monitor actual tyre pressure.

Either of these systems wont be affected by any mileage discrepancy within the cars modules.

 

[cbg-host]

What? :? Tyre warning?

in the photo
DSC (DynamicStability Control) Tyre defect indicatorKilometer reading (mileage) penultimate warning

Isnt it the mileage reading when the warning happened? It could be the module itself or tyre pressure loss? Its my understanding..

So i was guessing the warning happened at 96k km before rolling back milage. The current real milage is bigger than 96k km.. might be 110k 120km or more I dont know..

 

[AnubisZed]

Ahh, right. I don't use Autel, hence my confusion. :headbang:

Could still be the same, a used DSC, from a higher mileage car, with an original fault that wasn't cleared (stored fault).