Date: Sat, 13 Apr 2002 21:22:52 GMT From: hohnopsamlid.invalid (Goran Larsson) Subject: Re: 9-5 Headlamp Bulbs
In article <ubgtsv31sdeeb6nopsam.supernews.com>, Ken Freeman <kenfreemannopsamlepc.com> wrote: > Is anyone else tired of frequent failures of headlamp bulbs (H7 type > halogens) on these cars? Mine is a '99, and I've replaced both low beams > three times. The expected life for a standard quality H7 lamp is 550 to 600 hours. A high quality "+30%" or "+50%" H7 lamp is 250 to 300 hours. This is at the standard test voltage of 13.2V. A cheap low quality H7 lamp of suspect origin may have an even shorter life. > Is the voltage just too high? A voltage that is 5% higher than 13.2V (13.9V) will reduce the life by as much as 50%. > Does anyone know of a ballast or other gadget that would stabilize or > optimize the bulb voltage for best life? Reducing the voltage by 5% will increase life by up to 50%. I run my low beam H7 lamps at 11V. For a description of how I did this you may visit the webpage I wrote describing how it is done. My changes also modifies the high/low beam switch to operate like it does in the 9000, but the changes are independent and does not have to be done at the same time. > Any one else looked at these issues, and can offer some help? Go to < http://www.nospam.com/saab/modifications_en.shtml >. -- G–ran Larsson http://www.nospam.com