I need to give a credit to a customer's account so that I can apply it and a check to an invoice, how do I do this???

Any one know how to retrieve codes off this truck besides factory scanner? Have a OTC genysis

I have a 1998 Ford F150 4.2L V-6 Automatic that has a hard misfire (like a plugwire breaking down). With Genisys scanner comes up with 7 codes but most prevelent is the #6 cyl misfire P0306 and have swapped wires from 5 to 6 and replace coil pack. no change. Checked Identifix, of 34 posts -30 of whi...

Have a chevy 2004 Chevy silverado 2500HD w/6.0, 4WD, 4 Dr. He wants fuel filter changed; been on there 100k miles. Checked from tank to intake manifold, nothing but steel lines. Is it on top of tank or in the tank? Checked on identifix and it shows it along driver's side frame rail where you would t...