No DRLs

someotherguy said:

That's what it's *supposed* to do...whether or not you can tell with the naked eye, dunno. Might take a professional light meter or some such...or even simpler, maybe a clamp style meter over the harness leading to the lights and compare to normal headlight function. It may also be that the current is PWM, which is why you see discussions about LED's (and I would bet HID's too) not being suitable for use as DRL's.

EDIT - yeah, just checked a spare manual I had laying around - according to the 1996 GMC Sierra user's manual, "The DRL system will make your headlamps come on at a reduced brightness when: * the ignition switch is on * the headlamp switch is off * the parking brake is released"

I had to check because I don't think it's necessarily a written rule that all DRL systems that utilize the low beams will operate them at less brightness than normal. It only made sense to me though because of the diode module. They're using it to step down the voltage, which is also why it's on that heat sink.

Richard

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df2x4 said:

Sorry to derail this slightly but I'm curious, is this something you've checked? I've seen a few people post this but I can't tell a difference between either of my 97s DRLs and low beams. Never got the multimeter out to check because it's across town in my broken truck.

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Bob L said:

The reason I pulled the fuse on DRL is I like to be able to flash my lights to passing trucks or someone trying to turn left in front of you. With DRL activated I need to turn on lights then blink high beams, to much effort.

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