I have a 99 F-150. Recently i started my truck and it blew a spark plug which caused the service engine soon light to come on.I had it taken to a auto machine shop and had that prob fixed.The mechanic said he could not get the service engine light to go out his computer was not picking up any codes so he could not reset it. I pick my truck up tomorow morning im going to disconnect the battery for a few minutes if he already didnt.What else can i do?

 

Maybe check to see if a fuse is blown. If the cigarette lighter does not work, the scan tools can not communicate with the PCM.

 

If you mean at service oil life.
Hear you cand find the full procedure how to reset oil service light Ford E 150 Series. If you like to reset any maintenance oil light after an oil change. Or reset check engine light, airbag light, inspection key or insp errors when maint reqd, for Ford cars include all Ford F Series. Or any warning light for service reminder which appears on the display.

Reset oil service light Ford E 150 Series | Reset service light

All information is taken from the Ford E 150 Series owners manual.