Electronic truck warning signs on Rimutaka Hill Rd are under scrutiny by Wairarapa commuters, who are claiming the warning system is not working well enough.

New Zealand Transport Agency regional performance manager Mark Owen confirmed a small number of people had expressed concerns over the signs, which were installed five months ago on three narrow corners on the Featherston side of State Highway 2, as to whether they were working as they should.

The signs, powered by solar energy, are designed to warn motorists of an approaching truck, trailer or large vehicle.

There are monitoring devices along the road that detect the height of a vehicle and as a high-sided vehicle such as a truck and trailer unit passes, the electronic warning sign further up the road should flash to warn oncoming traffic that a large vehicle is approaching the corner.


However, some drivers have claimed online that the signs do not appear to be working properly, flashing when there is no vehicle and not flashing when there is.

The issue was discussed this month on the Wairarapa Commuters Facebook page, on which Peter Jackson posted, "so what's the deal with these flashing lights on the hill that are supposed to indicate that an approaching truck is just around a sharp corner?

"In my view, they don't work too well, having just about been taken out by a semi halfway into my lane this evening," he wrote. "Not a flash."

Meanwhile, Josh Coe said he had "met a number of trucks with no warning" along the stretch of road.

Mr Owen said the agency was monitoring the system and making adjustments as necessary. "The timing of when a large vehicle is detected and the signs starting to flash or the length of time they flash are two of the things we are tracking and, as necessary, adjusting."