The "Service" Lite comes on for a minute or so after starting the car. It had a 2-2-4 error in the diagnostics of the non-turbo Bosch B230F engine. I cleared it, started the engine, and the "Service" Lite still comes on for about a minute. I rechecked the diagnostics and they were all still error free (1-1-1) in sockets 2 and 6. Why does the "Service" Lite still come on? Thanks.

Are you looking at the "Service" light that indicates that it is time for a routine oil change? That light will come on when you start the engine and then go out after a couple of minutes. Normally, an engine "service" light will stay lit and not go out as you start to drive. On an '89 740 the oil change reminder "Service" light is reset manually pushing a reset switch on the instument panel.

JD,

The Service light is often confused with the Check Engine light. The Service light comes on every 5K miles as a reminder to change your oil. It simply needs to be reset and is no indication of trouble. One my 95 940 the reset shaft is located near the lower left hand side of speedo on the clear plastic instrument face cover. Remove the rubber plug and carefully push the plastic shaft found under it in with a small phillips screw driver or some such implement. Then push the rubber plug back into position and you are set for another 5000 miles. Earlier 740's may have had a differant re-set point, I can't recall, but if your 89 has the small rubber plug in the transparent guage face/with reset pin under it, you can reset the service light easily. At any rate, the service light being lit for a minute or so after starting is no indication of trouble. Hope this helps.

PS: Found this in the archives with info you may find helpful.
http://www.brickboard.com/ARCHIVES/1998JAN/7733.shtml