How to disable Gen1 DRL Daytime Running Lights

While DRLs are great where you need them (northern countries, rainy places) some people don't want them on all the time. The Gen1 Prius (2001-2003) with Factory DRL's is a bit a pain to defeat. You cannot just pull a fuse or relay and the main DRL relay is a complicated unit that is burried far far under the dash.

The easiest way I've found to disable DRL is to cut a wire under the passenger side engine room fusebox. Under the fusebox is a junction point butt splice (E2 on the wiring diagram). It has 2 Red/Black and 2 Red/Green wires all tied together with black shrink tubing and a "ring bump" around the end. If you don't see the butt splice you may have to unravel some of the electrical tape to expose it. If you cut the Red/Black wire with silver dots the DRL feature will stop working, but headlights will work normally if you turn the headlight switch on.



If you strip the ends of the cut wire and put male/female connectors you can re-enable them easily at a later time....perhaps disable for summer and enable for winter months. You could also extend the cut wires and install a more accessible toggle switch.

 

You either cut the wrong wire or something else going on with the car, check all fuses/relays/switches/wiring harnesses related to headlamps. You may need to study the wiring diagram and use a multimeter to trace and troubleshoot your car. If your car has factory DRL the wiring diagram is below. Cars without factory DRL are wired differently so you'll need a different wiring diagram.