From my point of view its better goes dead compare to wrong tunnel projections ...
... everybody knows GPS only useable in open clear sky ... n better get something else
to guide if u cant get it ! ... BTW the road sign is very clear ...
just follow ...
Everytime some of us lament the lack of "tunnel projection" or whatever it is called, in Garmin, it is misunderstood and sometimes ridiculed, completely without any basis. So, here I am, doing just a one-time explanation.
Of course, all of us know that GPS will not work in tunnel. This need not be repeated. We are not asking for GPS to work in tunnel.
When you need to get from Point A to point B (say from Hougang to Shenton Way), the GPS will route you a certain way, and you follow. Then it takes CTE South and you follow. Then the tunnel suddenly appears and the device goes dead. Then you tell me: WHICH EXIT TO TAKE? There are 5 possible exits and the display shows nothing. If you press preview route, it shows NO ROUTE AVAILABLE. In the end, you have to guess which exit to take, or maybe drive all the way to the end of the tunnel.
In the TomTom, the device does not go dead, but goes into "offline" mode. The screen greys out, telling you satellites lost, but it continues to enter some sort of simulation mode, probably based on your last known speed and route plotted. Then it guides you to take which exit to take. No rocket science here. The exit is based on your planned route, as calculated before you entered the tunnel. Of course, since it is approximation or projection, it may not accurately reflect your action location in the tunnel. But it does its job to guide you out of the tunnel, according to the route you were supposed to take. The moment your car leaves the tunnel, the device reverts back to normal operation mode.
You get it?