2008 H2, DRLs not working, changed bulb, checked fuse

[baldfox]

Another problem, I bought some replacement LEDs for my DRLs on the front of my H2, but they don't appear to be working. I replaced one bulb and inspected the original style bulb and it looked ok, i.e. the filament was still intact. I put the LED in expecting them to work, and nothing, tried a second LED and nothing on that either... I know they only come on in the day time (am not looking to do or have i done the DRL mod), and I also checked the 10A fuse in the fuseboard which is supposedly for DRLs. If i recall i checked the fuse here shown here (26):

http://www.*******club.com/forum/vie...php?f=3&t=6751

Again, looked intact. I just dont see the DRLs come on at all during the day.
As it stands now, I have a new LED on the passenge side, and an existing bulb on the driver side, neither working. Any suggestions guys ?

I've checked during the day whilst driving, i.e. not in park, and it wasn't on, neiher were the headlights (they set to auto).

Any advice gratefully received.

[HUMTECH]

check to see if you actually have power at fuse 26 with a test light, if not the internal relay in the fuse block is bad and will need a new fuse block (under hood fuse block)

[baldfox]

Originally Posted by HUMTECH

check to see if you actually have power at fuse 26 with a test light, if not the internal relay in the fuse block is bad and will need a new fuse block (under hood fuse block)

Sorry for the late response, I'll check it out.
Forgive the silly question, but do i just hook up both sides of a test light to either end of point 26 where the fuse would be ? If that is indeed the case, do i need the engine running etc ? Funny, years of messing round with wastegates, and turbos, (even rebuilding a warped head on a car) and yet have never really messed around with electrics.... i feel like a duck out of water. If the engine does need to be running, would i need the thing out of park and say into neutral, with sufficient daylight to simulate when the DRLs would be on normally- or am i getting the wrong end of the stick here how relay's work ?

If that is indeed the fault, do you know how painful it is to replace the fuse block ? Is it relatively hassle free, or am i better heading to a GM "Stealer"...

[HUMTECH]

Hook test light to ground then start truck and put it in gear(you need to have dtrl's on to activate relay. also need to make sure bcm is commanding them on, BCM supplied the ground signal to the lamp relay from connector x4 pin 23. That's the black connector at the bcm