How do i fix the Timing jumper?

The tech probably noticed your idle was too high because of a timing issue. You will need to adjust the idle before you can adjust timing. To do this, you will need a jumper wire go into your diagnostic plug. ( timing jumper) Inside the diagnostic box, look for terminal ten. The location is listed on cap. If not there, it's the one on the top row 2nd from right.Connect your jumper wire to this and then other end to a good metal ground point. If you can't find one, just connect wire to negative terminal on battery.You should then hear engine idle drop. Don't worry this is normal, all you need to do now is to adjust the idle to manufactures spec which is 750 to 850rpm (roughly) once that's done now you can adjust timing same as before, keeping the jumper wire in diagnostic plug as above and adjust timing using timing gun. The reason for the jumper wire is to disconnect the ECU so you can do service adjustments

I never heard of it but maybe some one here else here will know...