How to test the Rear Wiper Motor

On my Explorer 2000 EB, V6, SOHC, the rear wiper would work only part time, the washer pump would always work but not the wiper itself. If I would pull on the
spindle of the wiper, it would start working again, for few more days only to go bad again. I have checked the fuse for the wiper motor also, all is fine.
I got tired of it and took apart the trim and the wiper assembly, with the switch in on position, if I try to detect any voltage across the two terminals of the motor, there is none. If I check the voltage on the pins of the connector (motor disconnected) there is 11.x V across two of the pins ( 4 pins total).
I took the motor out and applied 9V DC to its terminals, it makes some noise but does not move the spindle.
How do I make sure that it is a bad motor before ordering a new one, no one has any in stock.
Thanks
Matt
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Anonymous wrote:

It sounds like the wiper motor is done for. You should acvtually get 12.xx volts across the connector but if applying voltage to the motor doesn't move it... Sounds like you need a motor, pretty common on Explorer rear wipers.
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12VDC motor. Wiper motors draw a few amps, so a small 9V battery eliminator or similar supply isn't going to have the juice to turn it. You could try connecting it directly to the car battery and see what happens, making sure you have the polarity correct. Good luck! SC Tom
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' '> '> I took the motor out and applied 9V DC to its terminals, it makes some '> noise but '> does not move the spindle.'> 'Depending on what you were using for a power source, 9VDC may not spin a '12VDC motor. Wiper motors draw a few amps, so a small 9V battery eliminator 'or similar supply isn't going to have the juice to turn it. You could try 'connecting it directly to the car battery and see what happens, making sure 'you have the polarity correct. 'Good luck! ' SC Tom ======================================================
You are right, my source was not capable of delivering Amp, it could only deliver mAmp. Anyway, I used a better source of power and found the motor to be working, I also noticed that it is the polarity reversal that reverses the direction of the motor and brings the wiper back. The wiper still des not work when connected to vehicle wiring, the issue now is that a Relay has to be involved to run the rear wiper.
Interestingly, I only see one relay noted in the manual that is designated as the Windshield Wiper Hi/Lo, Run/Park relay, there is none for the rear wiper, unless the same relay operates wipers on both ends.
Could someone kindly direct me, as to what should I do, in a nutshell, my rear wiper motor tests OK, the wiring that connects to the motor, has power on it (11.xV) but the wiper does not work. My thought is, the rear wiper relay may be bad, but the manual does not show any relay for the rear wiper, only shows for the windshield wiper.
Tia
Matt
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Anonymous wrote:

body to hatch / tailgate ... i would strip the door cover off and pull wires thru and check em under the rubber boot where they bend
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'Anonymous wrote:
'> '> ' '> '> '> '> I took the motor out and applied 9V DC to its terminals, it makes some '> '> noise but '> '> does not move the spindle. '> '> '> 'Depending on what you were using for a power source, 9VDC may not spin a '> '12VDC motor. Wiper motors draw a few amps, so a small 9V battery eliminator '> 'or similar supply isn't going to have the juice to turn it. You could try '> 'connecting it directly to the car battery and see what happens, making sure '> 'you have the polarity correct. '> 'Good luck! '> ' SC Tom '> ======================================================= '> '> '> You are right, my source was not capable of delivering Amp, it could only '> deliver mAmp. Anyway, I used a better source of power and found the motor to be '> working, I also noticed that it is the polarity reversal that reverses the '> direction of the motor and brings the wiper back. The wiper still des not work '> when connected to vehicle wiring, the issue now is that a Relay has to be '> involved to run the rear wiper. '> '> Interestingly, I only see one relay noted in the manual that is designated as '> the Windshield Wiper Hi/Lo, Run/Park relay, there is none for the rear wiper, '> unless the same relay operates wipers on both ends. '> '> Could someone kindly direct me, as to what should I do, in a nutshell, my rear '> wiper motor tests OK, the wiring that connects to the motor, has power on it '> (11.xV) but the wiper does not work. My thought is, the rear wiper relay may be '> bad, but the manual does not show any relay for the rear wiper, only shows for '> the windshield wiper. '> '> Tia '> '> Matt'i know its only 5 years old but the wires could be broken leadiing from 'body to hatch / tailgate ... i would strip the door cover off and pull 'wires thru and check em under the rubber boot where they bend ==================================================== I checked the wires, good as new. Another interesting thing I noticed. If I check the voltage on the wiper motor connector pins (with digital multimeter), it is 10.65 V when the wiper switch is on and 11.85 V when the wiper switch is off.
I have found relays, there are three of them, wipe up relay, wipe down relay and park relay, I did try to switch them around to see if wiper would work, no luck, did not test the relays as such.
Matt
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Anonymous wrote:

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