Crickett
10-22-2011, 05:28 AM
So, here's an interesting one for the Family's troubleshooting minds:
(Quick background & definitions: the two types of flat-tire monitoring (FTM) systems from BMW are a direct pressure-sensing system with transmitters in each wheel, & a DSC/ABS-based system that senses differences in wheel speeds & interprets that as a flat. I'll call the pressure transmitter system "RDC" & the DSC-based system "RPA".)
My ZHP did not have the FTM option from the factory. I have no FTM reset button on my panel:
http://tcholo.net:8080/images/bmw/FTMbutton.png
but I do have the light on the instrument cluster (it lights up during a cluster test). http://tcholo.net:8080/images/bmw/FTMlight.png Aside from the mentioned cluster tests, I have never seen the FTM light illuminated.
After getting DIS all set up on a spare laptop & reading about potentially being able to enable RPA flat-tire monitoring (http://forums.bimmerforums.com/forum/showthread.php?t=1499451), I gave it a shot, but couldn't get it to work. I didn't get any change in anything: no cluster light, no access to the RPA portion of DIS/INPA, etc.. I left the option coded in my vehicle order, thinking "if it didn't do anything, no harm in letting it stay 'enabled'".
Now (after my accident & repairs), I have a continuous red FTM light! I've hooked up DIS, checked for error codes (none), & reset the calibration values (equivalent to using the normal reset button). After doing so, the light goes amber (as it is supposed to while being reset). Normally at this point you drive off & the RPA recalibrates its "normal" values. My car's FTM light stays amber for about 5 seconds before it returns to red (with an accompanying warning beep); I don't even get a chance to get moving. This makes me believe that the DSC unit is receiving erroneous signals (or not receiving expected signals), causing it to display a flat tire warning. I subsequently checked the tire speed sensors in DIS & they all function correctly.
Short of removing the RPA option from my vehicle order, does anyone have any ideas of where/what to check for errors to get the RPA FTM working?
(Quick background & definitions: the two types of flat-tire monitoring (FTM) systems from BMW are a direct pressure-sensing system with transmitters in each wheel, & a DSC/ABS-based system that senses differences in wheel speeds & interprets that as a flat. I'll call the pressure transmitter system "RDC" & the DSC-based system "RPA".)
My ZHP did not have the FTM option from the factory. I have no FTM reset button on my panel:
http://tcholo.net:8080/images/bmw/FTMbutton.png
but I do have the light on the instrument cluster (it lights up during a cluster test). http://tcholo.net:8080/images/bmw/FTMlight.png Aside from the mentioned cluster tests, I have never seen the FTM light illuminated.
After getting DIS all set up on a spare laptop & reading about potentially being able to enable RPA flat-tire monitoring (http://forums.bimmerforums.com/forum/showthread.php?t=1499451), I gave it a shot, but couldn't get it to work. I didn't get any change in anything: no cluster light, no access to the RPA portion of DIS/INPA, etc.. I left the option coded in my vehicle order, thinking "if it didn't do anything, no harm in letting it stay 'enabled'".
Now (after my accident & repairs), I have a continuous red FTM light! I've hooked up DIS, checked for error codes (none), & reset the calibration values (equivalent to using the normal reset button). After doing so, the light goes amber (as it is supposed to while being reset). Normally at this point you drive off & the RPA recalibrates its "normal" values. My car's FTM light stays amber for about 5 seconds before it returns to red (with an accompanying warning beep); I don't even get a chance to get moving. This makes me believe that the DSC unit is receiving erroneous signals (or not receiving expected signals), causing it to display a flat tire warning. I subsequently checked the tire speed sensors in DIS & they all function correctly.
Short of removing the RPA option from my vehicle order, does anyone have any ideas of where/what to check for errors to get the RPA FTM working?