From RISKS DIGEST, another tale among many such:
Date: Wed, 1 Aug 2007 14:21:43 +0200
From: Erwan David
Subject: Driver follows GPS when he should not
On 22 Jul 2007, a Polish bus had a grave accident in Vizille (France). The bus used a road with a 14% (1/7) descending slope, it seems its brakes went too hot and could not stop the bus at the end of the slope.
The inquiry made appear that the driver blindly followed the indications of is GPS receiver, ignoring the 11 signs forbidding him to use this route.
Risk: always relying on technology, even if used a little bit out of spec.