Chrysler Repair: power seat switch 92 LaBaron Landau, voltage polarity, jumper wires

Question
hello roland,
first off my power seat switch is completely workable except the that it doesnt go back, it moves in all other directions but back.  i thought it is a bad/dirty/coroded conection in the switch, but i cleaned it and now i dont know what to do. is there a way to put the seat back manually, or switch a wire to make it go back? if not i can always buy a new switch

Answer
Hi Mike,
If I am not mistaken, the motors are reversible by simply reversing the polarity of the 12V applied to its windings, so if the seat moves forward and doesn't move back then it is more likely a switch internal contact rather than a motor problem. The wiring diagrams and the schematics of the switch system don't exactly agree so I can't easily describe the testing/jumping based on physical location. But the colors of the wires involved are very clear. The +12V from the battery comes to the switch on the red wire and the ground wire to the - post of the battery is the black wire. The wires to the fore/aft motor are red/light blue and yellow/light blue. So if you have a couple of jumper wires you could disconnect the plug at the switch and jump between those wires and verify that the seat will go in both directions (always jump one of the solid color wires to one of the bicolor wires, and then reverse the polarity; never jump between the red and the black which would be a dead short across the battery and blow the circuit breaker).  If that makes the seat move for and aft, then the problem is inside the switch. If not, then there is something strange about the motor because if it is working in one direction it should reverse if the voltage polarity is reversed. By examing the location of the wires on the plug, you can then test the switch by matching up the locations of the wires, and testing for continuity that matches what I described as the jumper connections necessary to make the seat move. You will probably find that there is a bad connection inside the switch that will fix your problem. Use electronics spray cleaner from an electronic supply store.
Roland