Hi all,

So I bought an 04 545i w/ 6MT awhile ago, to replace my 745i. I love this thing. Beautiful, fast enough to be fun, etc.



The seller explained to me that it had the ABS & DSC lights lit up because the rear tires were 255/45/18s, and the fronts were 245/40/18s. I checked around a bit, saw that this would indeed happen, so I ordered some wheels and a pair of 275/35/18s for the rear.

I had the wheels and tires installed today. The wheels were 18x8 all around, so 275/35/18s were a bit wide for an 8" wheel. They fit, though. And voila: the ABS and DSC lights are gone! It did, however, raise a few other issues:

• "Flat tire" TPMS warning pops up in iDrive. This never happened before, is it because the rear tires don't mount perfectly on the 8" wheels?
• When going around tight corners (honestly, any more than completely wide corner above ~70 mph) the car will kick traction control on for a split second and bring the car back into line. I could see this getting dangerous when I actually AM going around a tight corner; it makes tight turns almost impossible to hold.

Any ideas?

 

Do the new wheels have TPMS sensors installed? Did you reset the TPMS sensor in iDrive?

 

This is a 04, no sensors in the wheels. The TPM system works of the ABS system, looks for difference in wheel speed, rpms, between all 4 wheels. Would sugest resetting TPM system and go from there.

 

Do I need to reset it in INPA? Or do I use the speedometer reset button?

 

Also, do you think that putting 245/40s on the rear will cause the ABS/DSC lights to trigger again? Or will the car be fine with a square setup?

 

the flat tire monitor is reset from the idrive, look for it in the settings page.

I'm new to BMWs, but i've read a bad alignment or wrong tires can cause ABS/DSC lights.

 

The tires need to be inflated to the proper pressure and only after the car ha been sitting for some time. Ideally in the morning when outside temps are lower. After checking the pressure, go to the Idrive and reset the TPM with the engine running. Once reset drive off so the TPM can calculate. If the engine is stopped before the TPM calculates - start over with the reset.
Good Luck.