Anyone using the A14 this weekend and early next week is warned it is due to be closed overnight in each direction.
The eastbound carriageway between junctions 20, Ellington, and 21, Brampton Hut, will be shut between 10pm and 5am, from Saturday (March 7) for two nights.
And westbound, between junctions 24, Godmanchester, and 23, Spittals, will be closed from 10pm and 5am from Monday (March 9) for two nights.
A spokesman for the Highways Agency said the A14 needs to be shut so four signs which show messages for drivers can be replaced.
There will be diversions in place. Eastbound traffic will be diverted back along the A14 westbound to junction 13, onto the A605, A1139, A1260, A15 and B1043 southbound to re-join the A1 at Alconbury and A14 at Brampton Hut.
Westbound traffic will be diverted back along the A14 eastbound to junction 32 and via the A428 and A1.