I'm having some electrical system issues with my 2004 Yukon XL Denali. I purchased it 2 months ago, and the previous owner had aftermarket halo headlights installed. In order to avoid putting a switch somewhere inside the vehicle, he just had them wired to the daytime running lights. The driver side daytime running light was burned out when I purchased the truck, and that had to be replaced to pass inspection. That same light just burned out again...in two months. I'm also having quirky problems with the memory seat settings. Sometimes when I put the "Driver 1" key in, it says "Driver 2" on the console, and sets the seat and mirrors to "Driver 2". And the same "wrong driver" situation occurs with the "Driver 2" key every now and then. Sometimes it will display the correct driver for the key, but give me a seat and mirror config that is slightly different from what I use. Also, the seat heaters come on sometimes when I start the truck. And, when I put it in reverse, sometimes the "curb feature" works and sometimes it doesn't, but whenever it does work, only the passenger side mirror points down...the driver side mirror will point upward. The driver side mirror works fine with the controls on the interior of the truck...so the wiring can't be wrong on the motor/switch. Oh, and I almost forgot...I had to have the water pump replaced last week (I'm having great luck...aren't I?). The "Engine Coolant Hot" warning popped up on the console, but I never got a "Low Coolant" warning, even though it was about half a gallon low. Has anybody else had problems like this? Do I need a new control module? I'm going to start with disconnecting that "halo" feature from the headlights to see if that makes a difference.