S14 Window Motor Testing

[DirtyS14]

Well guys, I have searched and the stuff I found answered many of my questions... but i have one more.

My driver's side window has been non-functional since i bought my car, its a 95 240sx. I saw the article (http://www.nicoclub.com/articles.php?id=245266) about the window amp repair.... when I opened up the amp, i found that the circuitry is different and there are no contacts as shown in the pictures.:duh:

So I tested the window motor. I tried testing it with a 12V, 6A battery charger. The motor spun around once, very slowly and then stopped. Then I switched the contacts and spun it around in the other direction. Again it did about one revolution very slowly and then stopped. After that it didn't do anything. Does the motor need more current/voltage to spin properly? Or have I sent it to hell?

Either way I am replacing the amp. Also the passenger's side assy works fine, even when the amp is not plugged in. :)

[idlafie]

Nice Repair link....I'm surprised your amp didn't match. You might want to take a picture of the window amp & post it here just so we can get an idea of what yours looks like in comparison to the one on the repair link.

As for using a 12volt 6 amp battery charger to power your motor, that was a good idea. Although I'm not sure if the 6amp was enough to actually run the motor. Best way to test your power window motor is remove it from the window regulator & use your actual car battery to provide power to it to test it. That's usually enough amperage in your car battery to run your power window motor. If you use TOO much amperage, you'll usually know cuz the windings in your power window motor will burn up & you'll smell a metal burnt smell. I don't think 6 amps is enough to power your power window motor. So you should be okay there.

If you can get your hands on a volt/ohm meter, you might want to check your power window switches just to make sure there are no bad contacts or electrical shorts in the driver's side portion of the switch. If the switche turns out okay, then chances are it's your power window amp.

Anyhow, hope this helps....Good luck on the repair...

ID

[DirtyS14]

Thanks so much for your help, +1 rep! I'll try to find some other way of testing the motor.

Here is a picture of my amp.

http://img.photobucket.com/albums/v608/amaank/PC010225.jpg

I will certainly check the switch. The thing is... when i press the switch it makes the amp go click... so I assumed that the switch was working. It is a little spongy when you push it down compared to the pass side though, I'll check it out.

[projectRDM]

I always use a drill battery, 12V-18V works fine, amperage doesn't matter. If it does turn a bit then binds, the motor is bad. It should freely spin several times in each direction.

[DirtyS14]

I always use a drill battery, 12V-18V works fine, amperage doesn't matter. If it does turn a bit then binds, the motor is bad. It should freely spin several times in each direction.

Ohhh, I have 18V drill battery. I'll try it right now.

I think it might be binding but maybe not.

Thanks for you help! :love:

[idlafie]

Russ...you're a GENIUS!!!....Never would have thought of using a cordless drill battery....Genius....pure genius!!....hahahaha...

Any Dirty, you might want to try replacing your driver side switch. That "spongy" feel on the switch can leads to the switch burning out the power window motor and or the amp. The switch doesn't actually go bad, but the plastic tab on the underneath portion of the switch button does. 95 S14's driver side switches are known for this.

On a GOOD switch, it will have a "stiff" feel. When you press down on the switch, the switch button pops back into the neutral position after you release it cutting off electricity to the power window amp & motor.

On a bad "spongy" switch, sometimes the switch button doesn't pop back into the neutral position unless you pull it back with your fingertip. Because the switch button "sticks" in the ON position, the switch continues to provide power to the window amp & motor, that the reason you're hearing the click. After a while with the power staying on to the window amp, the window amp starts to burn out because of the constant electricity going to it. The circuit is only supposed to provide power to the amp & motor to get it to go up or down. It's not designed to be on all the time...a "spongy" feel is often an indicator that the switch button could be sticking and providing electricity all the time to the amp & motor causing it to burn out.

Anyhow, if Russ doesn't tell me to shut the hell up already, make sure to replace the switch after you get your amp / motor problem repaired. If not, you'll burn 'em out all over again.

Anyhow, hope this helps....

ID

PS:
The picture of the etchings on the green circuit board you posted looks exactly like the etchings on the one in the Nico Forums except yours doesn't have solder all over the spots where the circuit board etching broke. I'd have to look at the circuit board in person to see if there's a short in your circuit board.

[DirtyS14]

Cool thanks for your help!

I will try replacing the amp first and then the rest of the crap. I think my entire driver's side assy is shot.

My switch is spongy, my motor might binding and the stupid amp is dead. Methinks it is time to spend some money.

Thanks again guys! :bigok:

[projectRDM]

Correct. The limiter for the circuit is built into the switch, if the switch is bad the amp and motor will continue to see current as long as the switch is 'at rest'. The 96-up was redesigned just for that reason, moving the limiter into the main switch's body but after the relay (amp), therefore allowing the circuit to cool down even if the switch is stuck engaged.

Drill batteries work wonders, ever roll a car out of a trailer into a rainstorm with no battery or key, but with open windows? How about testing door lock motors, or HVAC motors? Just be sure to not keep current applied after the motor has ceased, 18V into a motor that's reached it's limit is not good for a prolonged time period.