cracker_1

I have searched and found nothing relating to this issue that I am having in my 88 4runner. The passenger window does not work. Bench tested the motor, works fine. When I use either switch, I am getting voltage on both wires that plug into the motor... Does anybody have an idea why this is happening? I have check the relay module, looks good, nothing burnt or broken. Cleaned the the master switch, drivers window works fine. Switches check out with multimeter.... I am stumped...

rustypigeon

I assume you are disconnecting the plug when you test it. When you do this, you are masking any areas in the circuit with high resistance, and the meter will show battery voltage. It shows voltage because the resistance of the circuit (probably a corroded connector) is only a tiny fraction of the infinite resistance of the disconnected plug. Google "voltage divider" if this does not make sense.

You need to backprobe the plug while it is connected to the motor. When you do this, you will probably not find enough voltage to drive the motor. Like I said you probably have a corroded connector upstream of the motor somewhere. Let us know what voltage you get when you backprobe the motor.

Edit: Here is a video that will show you what I am talking about. Notice how he gets 12v to the light plug, but the light still doesn't light?

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cracker_1

Good idea, will check it this afternoon and post results. Thanks for the idea

cracker_1

Tested leads to motor while plugged in, still have voltage on both legs. 11.8V and 10.1V respectively... Master switch issues, that I am not aware of? Tried another window module from another 4runner, no difference...

rustypigeon

What are you putting your meter probes to? Put your black probe on a good ground, not the terminal. Then you put your window in the down position, you should get positive voltage on the terminal that has a blue wire with a green stripe. When you put it in the up position you should get positive voltage on the terminal that has a blue wire with an orange stripe.

EDIT: If this test ok, then check the grounds. Put your meter in the ohms position. Keep your window switch in the neutral position, don't touch it. Keep one probe on a good ground. Disconnect the terminal from the window motor. BOTH terminals should show almost no resistance with ground. Less than 1 ohm. Don't touch the window switch when doing this, otherwise you will send voltage through your meter when it is trying to measure resistance. This can damage cheaper multimeters.

wyoming9

iTrader: (1)

Lets back up here .

How long has this not worked??

Have you checked the window regulator that it moves free in the track??

I have seen these get so dry they won`t move.

Have you tested the motor in the door bypassing all the control circuit??

I have had motors run fine with no load but fail when tested under load.

Just dieing from old age

cracker_1

tested the motor while in the door. Raises and lowers the window, no problem. Yes. I made sure I had a good ground. Tested both legs while pressing the switch, either up or down. Both legs, connected to the motor, showed power. It has not worked properly since I purchased the 4runner. Previous owner took out the electric windows and added manual regulators. I am trying to put it back the way it was.

rustypigeon

Did you have your negative multimeter probe connected to battery ground and positive connected to the connector plug when you checked it? If it does not show battery voltage when you do it this way, you found your problem.

You are working with a 12v system. It does not take much resistance to cause a problem when you have only 12v pushing the current through. If you have a battery charged to 12.5 volts, I would expect almost all of that 12.5 volts to reach the motor when tested dynamically as described above.

Punchy

Toyota runs a white and black wire back out of the door through the loom and grounds it to the body inside the cab (On 2gen 4R (3gen trucks) its connected at the dash crossmember bolts)

Sometimes this gets undone and not reconnected or painted and a bad grounding accures.

wyoming9

iTrader: (1)

Clean all the plug connections with contact cleaner and maybe a small screwdriver.

I had corrosion you could not see with the naked eye just about had me bring out the BFH

About where you are !!

IhateUSERnames

i got an idea! ditch all electric window/lock junk and go mechanical! i did any will never go back! to many headaches!