Daytime running lights

I have a 96 GMC Sierra. Recently I lost the daytime running lights. The instrument panel Icon is on but no lights.I checked the fuses they are OK, Is there a DRL relay and where is it located? All the manuals I have do not show it.

The relay is most likely not the problem, but it is located in the convenience center(inside the vehicle, drivers side, on the firewall, I think the flasher unit is there too) the DRL relay is on the bottom row. Most times it is the DRL diode that goes out, but the relay is cheaper and easier to replace

I have a 2004 Sierra 2500HD 4X4. My DRL's stopped working so I checked the bulbs and all the fuses and relays and they were all good. I took it to the dealer (under warranty) and they said the bulb sockets had burned out. They replaced the sockets and they are working fine.

The relay is most likely not the problem, but it is located in the convenience center(inside the vehicle, drivers side, on the firewall, I think the flasher unit is there too) the DRL relay is on the bottom row. Most times it is the DRL diode that goes out, but the relay is cheaper and easier to replace

I had my 1995 GMC looked at, it was the diode. I am not sure where it is located, just they told me they had to remove the dash to get to it. I need to replace my diode, but i couldn't wait for the part to get in the next day, because I needed my truck for work.
What I need to know, and where is the diode, and how much will it cost, and is it easily replaced?