zoulas

Hello gents, my first post here. I have 1986 Custom Cruiser wagon. The power seat motor just makes a hum when pressing any of the buttons, no movement. Is this a problem with the control buttons or the motor? Does this vehicle have three motors under the seat (like some other brands I have seen?) Is there a replacement motor available if this ends up being the problem.

Thanks, Aristotle

joe_padavano

There are three possible problems here, the motor is not running, the clutch is not engaging, or the plastic coupler on the motor has broken.

If you can hear the motor running but there is no motion, the coupler is the likely problem. This is very common - the plastic coupler deteriorates and breaks. Replacements are available.

Assuming the coupler is good, the most common electrical problem with these is the switch contacts. GM used to use a relay at the motor to reduce current through the switch, but as a cost-savings measure in the 1980s, the relay was deleted. Unfortunately, the terminals in the switch were not upgraded to handle the added current. The result is burned switch contacts. You need to get a wiring diagram for this car (it's in the 1986 Chassis Service Manual). You'll see that to move the seat requires two circuits to be closed by the switch - one for the motor and one for the clutch that operates a particular direction. You can remove the switch and use jumpers in the electrical connector to activate the motor and the clutch directly. If this causes the seat to move, the switch is bad. If not, either the wiring is bad or the motor or clutches are bad.

zoulas

Thanks Joe.