Try relay 209, it is located under the dash by the fuse pannel. I took that one out and made a sort of jumper to disable my DRL's. Hope this helped. Tomek
Check the bulbs Check the switch Check the relay
Yes, there is a headlight relay,
Check out www.realoem.com
Check the Fuse and/ or relay.
The switch or the relay, check the cheapest, or simplest thing first, which could be the relay, but the symptom points more to the switch.
Check Fuse Check Relay Check Power to Fuse, and relay both Check Switch, contuinuity
switch, relay ,light. use a separate relay for each light. switch sends power to relay, relay turns on light. the relay is so that the switch doesn't have to handle the power a headlight requires. auto parts stores have fog light wiring kits that come with all the parts you need, but they usually only use one relay, I always use two. there is a diagram here. http://www.rowand.net/Shop/Tech/images/HeadlightRelayWiringDiagram.jpg
check the headlamp relay most likely stuck
A 96 Bonneville should have a relay in the headlight timer circuit. Check the relay as it is most likely stuck and needs replacing
Check switch Check relay Check fuse in power distribution box under hood
You can find the wiring diagram for a relay position for a 1997 Mercury Sable in the owner's manual. You can also check local auto stores.
Whatever controls the relay must be broken, if everything beyond the relay works.