Instrument cluster tire size change Topic is solved

Post by **RickHaleParker** » 01 Sep 2020, 02:32

Best chance is to find another car with your current configuration. Read the tire value, then duplicate it .

If you email of the author of 850 OBD-II, he might have a some values from cars with the same configuration. That would give you a short list of values to try. You can also ask MVS member esl_97_850_T5. 850 OBD-II is based on work he did. Either one maybe able to data mine their database for a short list.

Post by **misha** » 01 Sep 2020, 11:55

I never tried h & m buttons to change C to F or 24h clock to am and pm...but it should also change readings on board computer for fuel consumption from km to miles.

Doesn't that changes also affect speedometer to read from km to miles and vice versa?

Post by **scot850** » 01 Sep 2020, 14:29

I have been wrong (according to my wife) before, but I thin this is not a signal issue as much as a gearing variance between AWD and FWD.

Now whether or not that can be adjusted via software or swapping the whole cluster for a FWD version is the answer I am not sure.

Neil.

Post by **mkc1** » 25 Sep 2020, 11:48

I tried most of the "normal" combinations for the B901 from the list at jonesrh.info with no joy. The cluster refused to accept some of them (scanning the cluster after programming showed that the value hadn't changed) and others didn't make much of a difference. In desperation, I tried the one from Misha's post -- B2, even though it seemed to be for an S/V70 rather than an 850. It did seem to fix the speedo, at least when the B90E value was set to 1E, but the tach showed too fast ... close to 1200 at idle and somewhat alarmingly high when accelerating. I could have lived with that, but after exchanging some PMs with esl_97_850_T5, he gave me some other values to try.

After trying several combinations, a B901 value of 22 plus a B90E value of 1E seems to give me accurate info on all the gauges. I also checked the odometer against kilometer markers on the highway and that seemed spot-on as well, at least as much as one could discern in 14km or so.

Thanks to everyone for their help!

Post by **abscate** » 25 Sep 2020, 13:48

And if you are desperate to get your cluster and tires to match, you can wrap your tires in duct tape

Post by **volvolugnut** » 25 Sep 2020, 14:32

abscate wrote: 25 Sep 2020, 13:48 And if you are desperate to get your cluster and tires to match, you can wrap your tires in duct tape

Can you provide information on the number of wraps needed? Would the wraps be radial or bias wrapped?
volvolugnuty