Electric gurus step in, weird issue?

[Nick Micale]

These damn cars still kick my ass after 30 years of messing with them, especially when is is an electrical issue?

My recent purchase is a 1986 T-Type that I plan to sell, and it has a driver side power window that will only go up. I figured the motor was bad so I pulled the door panel and removed the electric connector from the window motor and hooked it up to a new motor to check it first.

The new motor will run only in one direction, must be up, but when I check the connector with a test light power is there for both up and down by activating the switch. and figured it may be a bad ground,

I have no clue how to track for a bad ground in a window circuit?

A friend came by later and was telling him about this issue. We were messing with the switches and I tried the driver door switch and with that switch down, the pass window went down as he activated the pass switch?

Appreciate any ideas where to start?

 

[achalmersman]

Probably a bad master switch. Attaching the windows schematic (or did you already have it and do troubleshooting?)

Push on the toggle part hard while rocking back and forth

While pressing down on LH side master switch should see 12V on Brown wire to ground. If you do then check to see if while pressing switch down you have 0v to ground on the dark blue (motor must be plugged in for this test). If both those conditions are met then window should go down. If either of those conditions are wrong switch is bad. If you see 12v to ground on both wires with the switch down (specifically dark blue) the switch is not providing ground in the down position. Since window goes up motor, wires, and G187 must be good.

 

[turbo89]

These damn cars still kick my ass after 30 years of messing with them, especially when is is an electrical issue?

My recent purchase is a 1986 T-Type that I plan to sell, and it has a driver side power window that will only go up. I figured the motor was bad so I pulled the door panel and removed the electric connector from the window motor and hooked it up to a new motor to check it first.

The new motor will run only in one direction, must be up, but when I check the connector with a test light power is there for both up and down by activating the switch. and figured it may be a bad ground,

I have no clue how to track for a bad ground in a window circuit?

A friend came by later and was telling him about this issue. We were messing with the switches and I tried the driver door switch and with that switch down, the pass window went down as he activated the pass switch?

Appreciate any ideas where to start?

IS the switch reversing the polarity to the motor ? use a DVM

 

[Nick Micale]

Thanks guys, I will do what Andrew said first and change the master switch as I can easily do that in 5 minutes!

I am good with wrenches, not so much with electrical boxes or different colored wires?

Will post results tomorrow.

 

[Nick Micale]

A new driver side master switch cured the problem, thanks for the help!