hid headlights causing hvac problems

I am new to the forum. I am having problems with my HID lights causing problems heater and AC. I have a 1990 Olds 98 Touring Sedan with the Electronic Climate Control System. The heat works just fine with the lights off but when you turn on the headlights the heater control starts acting up, the display starts flashing on and off and giving me error codes . When I check the HVAC diagnostic codes it is giving me (AT) Ambient Temperature Sensor errors. I checked the wiring diagrams and it looks as though the AT sensor and right side headlights use the same ground. If I unplug that headlights the HVAC works fine, plug it in and it starts acting up again. I tried moving the headlight grounds and it still acts up. Is there a way to isolate the headlight ground from the HVAC grounds to eliminate the problem. Thanks Mark

The HID grounds for the controller, and ballasts, should be wired right to the battery negative terminal. The other ground and power come from the headlamp's harness, and stay...

Thanks Powerslave, I will do that this weekend. I finally found the boxs the lights came in. I purchased the HID lights from one of my Jobbers and I really can't find much info on the company. They are LUMINOUS 8000K The Ballasts are LBALLAST AC35 SLIM. The part number for the basllast is 3BB2GCMH13.... The bulb part number is 9004/9007HLANPAU133.

Thanks Again..

Mark

I have a HID kit I am installing into an '06 H2 SUT. IT comes with a controller, and two ballasts. It only has one headlamp harness to plug one of the headlamp plugs into the controller though. So, the fused 30AMP RED goes to the battery (+), ALL grounds to the battery (-). All that is left are the three wires at the headlamp plug, and that plugs into the harness to the controller. The controller is operated by the headlamp switch and high-beam switch, three wires; HI/LO/GROUND and they are isolated from the main power and grounds the controller and ballasts use. When in doubt, ALL grounds to the (-) battery terminal, or to a chassis ground post.

How did this turn out?