Nope, insurgents found a way around that a long time ago when convoys started including jammers. Hybrid detonation systems: radio arm the device outside of jamming range, mechanical switch detonated the IED once the vehicle triggers it.
This is why IEDs are so effective in asymmetric warfare. They are cheap and anyone can get parts =(
The first time I saw the results of an IED blast was a day after I arrived in Iraq. I had to shake a tree in order to retrieve the trousers of the guy who blew himself up planting the thing. That happened a lot. Making IEDs isn't very hard, but making a lot of them without eventually blowing yourself up is.