My wiper motor would not work also, i pulled it and did the jumper wire test, nothing... I took the entire motor apart and put back together ( note: getting the brushes back on the armature takes a LOT of patience , use a small hook tool ) Nothing, I took apart again and cleaned / sanded / polished ) the armature ? or whatever the brushes come in contact with, it worked ! test on a bench using the 12Volt jumpers, i used a batt jumper box. NOTE AGAIN ! This was a bit involved and PLEASE only try this as a last resort and ONLY if your comfortable with elec motors.... be gentle with the wires connecting the brushes. Thanks MopeCarGuy for the clocking info !!