A challenge for you electrical Guru's

The challenge is wiring a '03 Explorer Sport rear wiper motor to work with a 2nd gen 4dr. Or more specifically a 2000. So far I haven't been able to get it to work.


'03 Sport rear wiper connector


'03 Sport rear wiper wiring


'00 rear wiper wiring


What I have tried is:

2000 rear wiper plug.........................2003 rear wiper plug
Violet/Yellow (park sensor)---------> Violet/Yellow Pin3
Black(ground)---------------------->Black(ground)Pin1
...................................................Brown/White Pin2 --->Battery J. Box see '00 wiring diagram
White/Orange(wiper up relay-didn't use)
Black/Light Blue(wiper down relay-didn't use)

The '03 connector has the Brown/White wire which supplies constant power. The '00 doesn't have an equivalent so I connected Pin2 to the White/Violet wire in the battery junction box. It said constant power on the wiring diagram. Unless I misunderstood the diagram and it means the box has constant power and not necessarily the wire. At any rate it didn't work and I don't know where to go from here. So I hope someone with more knowledge can come up with a better idea.

this is assuing the gem module can handle this and it will operate the up relay without a park signal. it may say forget it. on the new 3 pin plug wires should be as follows
1- ground
2-blackk/Light Blue wire
3 - white/orange
then you need to locate the down relay and jump pins 2-3 of the relay and not install the relay

Do you mean to pull the down relay. Then jump the wires that lead to pins 2,3 of the relay? I'm not following you when you say not install the relay.

yeah the pull down relay remove it and jump pin 2/3 in the relay plug

briwayjones said:

Do you mean to pull the down relay. Then jump the wires that lead to pins 2,3 of the relay? I'm not following you when you say not install the relay.

Click to expand...

Indeed... jumper the pins in teh fuse box with a short piece of wire and a couple of spade connectors. That'll give you a hot power supply at the harness via the BK/LB wire.

The problem I suspect you'll have, however, is that the signal from the GEM to the relays is an alternating signal. (i.e. up for one second, down for one second) That'll leave you with an intermittent run signal on the motor, and no way to tell it to park either. The problems beyond that are numerous: Since you can't reprogram the GEM to make it work with the '03, you'll need to run wires direct from the switch. However, I doubt that the existing switch is capable of handling the current, so now you need a switch too. Since you're installing a separate switch, you'll also need a power source for it. None of that even addresses how the system will know to cut the power in the park position, so it'll stop in a different place every time (unless I'm reading the schematic wrong and it parks at the end of every swipe... can't tell for sure...)

I have to ask: Why are you doing this?

-Joe

gijoecam said:

I have to ask: Why are you doing this?

-Joe

Click to expand...

Hmm, this is getting more and more complicated all the time. If I run wires from the switch couldn't I just use the factory switch and use a relay in between? But then there is the park issues as you mentioned. Well wait a second, according to the '03 diagram it doesn't use the wiper up and down relays. So on the '03 does the motor know when to park itself? It's all together a much simplier wiring system than the 2nd gens.

I wanted to be able and finish and then make a post about it. But I got tired of fooling with the defectively designed rear wiper motors on the 2nd gens. I've replaced mine twice and they have both stoped working within a month. So I decided to replace it with a rear window from a '03 Sport which has the wiper on the window. I think it looks better too.

I've been staring at that schematic off and on for two days..... I think I have it figgered out.

It appears that the motor uses the input from the relay to start the cycle. Once the motor begins to move, the contacts inside it switch from 1 to 4, providing power directly from the fuse box, and the motor continues one full wipe. When the motor returns to the park position, the contact goes back to position 1. If the relay is off, the motor stops there. If the relay is on, the motor starts another cycle. Basically the GEM grounds the relay which initiates the movement, and the motor cycles one complete time.

Homor me.... if you've got a couple extra pieces of wire, connect the motor to a battery, positive to the BN/WH and ground the BK. Then, take the VT/YE wire and touch it to the positive side of the battery for a moment and remove it. The motor should make one revolution and stop. Touch it to the battery and hold it, and the motor should run continuously until you remove it, at which point it should then complete the cycle and stop.

Now, if that works, I can think of a couple of ways you might wire it up, but they're all going to have trade-offs.

If you wire the switch directly, you'll only have an on-off setting regardless of which way you connect it. I would think that you could use the OEM switch for this, but you would need to bypass the GEM and the relays to do so, and getting a wire directly from the switch to the back of the truck could prove to be tricky...

Now, if you used the OEM wiring, I think it just might work. Bypass the motor down relay as we mentioned earlier in this thread. That will provide constant power via the BK/LB wire to the BN/WH wire on the new motor. Then, connect the WH/OG wire to the VT/YE wire on the motor. You should be able to use the existing ground (assuming of course, that it's large enough to handle the motor current. If not, just run another one to a convenient grounding location). Then, when you switch the rear wiper on, the GEM will trigger the motor up relay for a second as it normally would, starting the cycle on the new motor. Depending on the timing of the intermittent cycle, it may work well. However, setting the rear wiper to the continuous cycle, there may be some issues with the timing of the relay, as I'm not sure if the GEM simply runs off a timed cycle, or if it looks for a signal from the park sense wire. If it's the former (as I suspect it is), it should work well. If it's the latter, we may need to jumper the VT/YE wire to ground to fool the GEM into thinking the motor re-parked itself. It may take some experimenting to get it to cycle the way we want it to...

Also, if the GEM cycles it based on timing, there may be some issues with trying to get it to run continuously.... you may find that the motor runs intermittently with funny pauses at the park position. There may be no easy way to overcome that though.... it could be done, but again, would require a wire from the switch to the motor bypassing the GEM and relay. Off the top of my head, I'm thinking you'd need to crack open the switch, solder a lead onto it, then feed the wire through the firewall and splice in underneath the fuse box, using a diode to prevent a back-feed and short to ground through the relay. Not too difficult or complicated, but could prove to be more work than it's worth.

Make sense?

-Joe

Does make sense. I'm planning on working on it again tomorrow. Thanks.

Ok I tried this stuff and it didn't work at all. I tested the motor to make sure it works and it does.

OK, so I was right about the impulse signal initiating the cycle, and it returns to the park position, correct?

If so, then are you sure you have constant 12V power at the connector on the tailgate? Did you jumper the proper two connections in place of the relay? Did you check for the intermittent signal from the GEM on the wiper up relay or at the connector at the tailgate? Did you run a separate dedicated ground wire for the motor and verify that the ground is, in fact, grounded?

That's where I'd start. If the motor is good, then the rest is just checking connections at the tailgate with a test light.

-Joe

gijoecam said:

OK, so I was right about the impulse signal initiating the cycle, and it returns to the park position, correct?

Click to expand...

Correct. If I ground it, put the BN/WH on +, and touch the VT/YE to + it will go one cycle and then park. If I leave the VT/YE on the + it will go until I remove it and then finish the cycle it's in and park.

gijoecam said:

If so, then are you sure you have constant 12V power at the connector on the tailgate? Did you jumper the proper two connections in place of the relay? Did you check for the intermittent signal from the GEM on the wiper up relay or at the connector at the tailgate? Did you run a separate dedicated ground wire for the motor and verify that the ground is, in fact, grounded?

Click to expand...

I forget I have a multi-meter now and didn't check to make sure I was getting the constant 12V at the connector. I did run a seperate dedicated ground, it didn't help. I jumped the proper two pins at the down relay. I'm not positive they were making good enough connections though. I had to modify one spade connector because the one in the relay is very narrow, plus very long. It wasn't connectiing very tight on that one. I'll have to see if I can get some spade connectors that will work better. I'll break my multi-meter out and try testing the things. How would I check for an intermittent signal at the wiper up relay using the multi-meter?

I'll get to looking at mine soon, maybe Saturday or Sunday. We'll figure something out to make it work. Regards,