testing a 3 spd wiper motor

[74fldart]

does anyone know a way to test a 3 spd motor out of a 74? i bought a supposedly good used motor but cant get anything out of it, i ran an extra ground wire to it and still nothing. I checked voltage going to the bulkhead connector and only get 9 volts but still shouldnt it run but slower. ive hooked up 12 volts to the wiper motor harness and it didnt make a sound but since there are 4 wires to choose from maybe i did nt get the right one. any suggestions are welcome, thanks

 

[RedFish]

Those wiper motors will reverse directions in mid sweep to park, meaning they are more complicted than earlier models. A factory service manual has several pages of dianosic proceedures for both motor and switch. Maybe someone would scan those pages for you. I wouldn't just stick current to various wires though. You might fry what was a good motor and/or switch.