Has anyone else been routed incorrectly under a low bridge yet with the new 2012 Q1 navteq maps?
Have installed the latest 2012 Q1 ftr files, but twice primo has tried to send me under a 10ft bridge despite the vehicle height being set at 13ft. I have also noticed that when entering a 7.5t restricted road, the warning message still refers to it as a "3.4t" restriction. Could this be down to an incorrect conversion by Navteq from metric to imperial measurements?

maa1506 wrote:Could this be down to an incorrect conversion by Navteq from metric to imperial measurements?

It's possible.
I've heard of that type of thing before with speed limits as they relate to the UK.
Or some mix-up on your device such as not maintaining the correct regional measurement settings.
You could try, as an experiment, changing your regional settings to metric, change your truck heights accordingly, then see what happens.

Speed limits are actually working all OK. The biggest problem is the low bridges, will give it a try though and report back, thanks

I looked into this a couple of map sets ago, and while you can change the displayed heights and weights to use different units of measurement, it's still not right and no amount of tweaking or editing gets anywhere near close, it must be down to the map data, one work around was to double or even triple the vehicle height entered.

OK, think I have found the work around for this which is as you suggested. Hopefully it will be of some help to others.
Today I set the vehicle height to 89ft so that it would trigger a warning message to every bridge that I approached. I noted the difference between the actual bridge height and what the satnav said it was. The ratio between actual and reported height was the same with all bridges. An example being a 14' bridge was reported by the satnav as being 39.97ft. I presume it's some sort of lost in translation error in the data.
The answer therefore is to multiply the actual vehicle height by 2.855 (or 2.9 to be on the safe side).
For example if the vehicle height is 12ft, entering it into to the satnav as 34.8ft should avoid routing under low bridges.
The weights difference seems a complete oddball as UK weights are in metric tons the same as every where else. However for some bizarre reason the weights difference works the other way. I discovered this one when the satnav tried sending me on a 15 mile detour to avoid a 38t weight restriction on the old seven bridge, despite the vehicle weight being input as 26t (the satnav said it was a 17t restriction).
The solution to this one is to divide the actual vehicle weight by 2.2, for example entering a 10t vehicle into the satnav as 4.54t should avoid totally unnecessary detours.

Excellent experimentation and detective work!

And yes, this may benefit other truckers. Thank you.
(I have saved your description/math, and may use it for others who have the same issues but may miss this thread....if that's OK with you)

Still.... MAKE sure you read the current road signs as the road or bridge may of been modified.
DO NOT rely on the Navi unit.

Bazzle