The service light stays on until you reset it. It is (from what I understand) a reminder switch. It always seems to come on at the most inopportune time for me. To reset the switch, follow the instructions below, completely and carefully. It is important to do it quickly and not let any time lapse after each blinking of the light, or else you will have to start over and do this procedure several times. At least that's what I've found with my car. Cut and paste these instructions to a test file and print them out...then keep that in your glove box. This is most helpful. ---Dave

How to reset the 850 Service Light (Prior To 1997)

1. Turn on the ignition without starting the engine

2. Open hood

3. Front End of the car on the left hand side you will find two small, black boxes

4. You will only be working on the one labeled A

5. Remove cover of box A

6. To one side you will see a wire with a plug at the end.

7. Box A has multiple plugs each labeled with a number.

8. Connect the plug to socket number 7

9. Push the black button four times

10. You Will get One steady Flash.

11. Push the button again once

12. Red LED light will come on

13. Push the button again 5 times

14. Red LED light will come on

15. Push the button once more and you should get a blinking light,

indicating everything is OK.