Wiper motor on relay

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I may have found something. Looks like the wiper motor gets it power from ACC. What if I put a relay on the ACC and feed it straight from the fuse block. Basically let the ACC act as the switch and the fuse block feed the voltage?
 
This is really not going to be possible, because the wiper switch is much more than a simple on/off device. There's a fair amount of interactive control between the motor and the switch. Not only does the switch contain a variable resistor, but it also reverses power to the motor when you turn it off, so the motor runs backwards to activate the parking pulldown cam in the crank arm linkage, until the motor trips its internal parking switch and cuts off (at the bottom of wiper travel, if everything's in proper repair and adjustment). This is also why it's not practicably possible to add an intermittent wiper control to the variable- or 3-speed wiper setups.
 
I have a voltage drop across acc. It is enough to affect the wiper motor but not enough to bother anything else. I have done everything I can think of to correct it but I have still not found a way to correct. So my hope is coming straight off the fuse block instead of the ignition switch will resolve it.

I have verified the wiper motor works with full 12v. I have not tried replacing the ignition switch though.
 
I'm still not sure what you mean by "voltage drop across acc". You have a voltage drop across the ignition switch? That's very common. If it's affecting only the wiper circuit (which seems unlikely, but you're near the car and your test meters and I'm not), then yes, you could install a high-current relay triggered by the ignition switch and let the relay handle the high-current switching to the accessory loads.
 
I measured the voltage across acc to ground and yes there was a drop but there was a further drop from ACC to the wiper switch. I would replace the wiper switch because I think thats where the issue is but I can not find a replacement.
 
Interesting development.

http://www.ebay.com/itm/PLYMOUTH-VA...5|Model:Barracuda&vxp=mtr&hash=item1e69170810

I found this on eBay this evening but this is not the switch I have. I do not have the piece hanging off the end.

I have been inside my switch when I cleaned the contacts and lubed them. The switch I have has an off, low, high and variable position, looks like bar inside the switch that the switch contact runs along. How do I know if I have the right switch.

This looks like the switch I have.
http://www.bradsnosmopar.com/nosmo19allpl.html
 
I don't know. The one in my 67 looks sortof like the ebay photo. I think you're barking up the wrong tree. Find would where the voltage drop is. One member just PM'd me that he'd found a broken "in harness" splice. This makes the 5th or 6th car in my lifetime that I've been somehow involved with a bad splice.

The path for your wiper is from the battery -- fuse link -- bulkhead connector -- ammeter circuit -- ignition switch connector -- through the switch -- back out the ignition switch connector -- to the feed buss in the fuse panel -- through the fuse -- and to the wiper/ switch circuit, and of course back out through the bulkhead.

So you need to probe major points and find out where you are actually getting the drop. Run the motor on high speed

Start by measuring the hot buss side of the fuse (you can determine by removing the fuse, which end is hot)

So measure from there to a good ground WITH THE MOTOR RUNNING and if bad, move back towards the battery, if good, move onwards through the wiper circuit.

Don't forget to check BOTH sides of the fuse in case the fuse or fuse clips are bad.

I assume you have some sort of diagram?

Here's the MAD article on ammeters:

main page:

http://www.madelectrical.com/

The article you want:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

and the important diagram:

NOTICE that AFTER the power feed from the battery comes through the bulkhead, goes through the ammeter, changes to BLACK, that there is what they are calling a "welded splice." This is a big factory splice, all taped up in the under dash harness, that as noted, feeds UNfused power to the headlight main circuit, to the hot fuse box buss, and the ignition switch which controls the "accessory" hot feed to the fuse box



amp-ga18.jpg
 
Well I replaced the ignition switch and it resolved some of the drop and the wipers appear to be working better but not completely yet. So I also want to replace the wiper switch. Does anyone know the correct mopar part number?

I stumbled on this part number 2770378 but it say 66-69 is it the same?
 
Okay so I finally got a chance to test my wiper switch and it is shot. So I ordered a new one from eBay plugged everything in and pop. The switch overloaded and now does not work. Damn it all to hell any ideas what might cause it? I could hear what sounded like a relay flipping back and forth. And when I initially turned it on the wiper slowly started to go then stopped.
 
What size fuse is in the wiper spot?

Could be wiper motor/ transmission going bad, or is VERY common for wiper shaft assemblies to bind up inside, dry, corroded. Pull the motor, and work the linkage by hand, see if it's free
 
I have put 12v to the motor and it will spin freely and I have moved the linkage by hand with very little trouble. As for the fuses I went through and replaced them all as per the service manual.

Is it possible the motor bogs down when ever it has to apply torque? Maybe something I can fix if so?
 
If it burned up the new wiper switch when you turned it on, You have a Dead Short (completely grounded) somewhere in the wiring between the switch & the motor.
 
Well hell. How can I track this down? Maybe disconnect the motor and then test each connector at the switch to ground? That should give me infinite if it isn't grounded right?

How about the other three connections? One is power but I am not sure about the other two.
 
In answer to your relay question, yes having the ign switch actuate a relay for ACC is smart. I did that recently when I repaired my dash harness. 67Dart273 is right about the welded splice (thick black wires) being troublesome. My wires were a little green there, so I sanded and soldered the connection.

Re wiper switches, I had several in hand for my 65 Dart. They look like the one in your "Brad's NOS" link. The original was a 1 spd, but I installed a 2 spd since it had the washer terminal (push on knob to spray). My 65 Dart's wiper motor is 1 spd, with 2 wires plus a body gnd. One wire is motor power (armature) and the other is "park".

The wiring diagram shows several more wires to the wiper motor for the variable speed option, which suggests the motor differs. They don't show a 2 spd option in the 65 drawing, so maybe earlier. I suspect that for 2 spd, the low-speed switch position just selects a series resistor, and the motor has the same number of wires. Variable speed is much more complicated. Slant Six Dan seems to know how that works. When searching for wiper switches, I saw amazing prices asked for variable speed switches.
 
Yes that is the problem everyone wants an arm and a leg. I stumbled on a thread on another site for JS Restorations that claims to rebuild these switches.

I spent some time with the service manual and tracked down all the connections. The following table shows the connector on the switch, the wire indicator in the service manual, wire color and then where it leads to. My wires under the dash all look good and are still factory wrapped so I doubt the ones that lead to the motor are the issue. I have a suspicion that it is the Back Up Lamp switch. Can anyone explain how it is used and also where to find it?

SW Wire Color Leads
B B1 White Back Up Lamp
F1 V4 Red Wiper Motor Field 1
F2 V5 Yellow Wiper Motor Field 2
W V10 Tan W/Tracer Bulkhead connector F Back Up Lamp
B V1 Pink Accessory Feed Fuse Block
A V3 Black W/Tracer Wiper Motor Armature
P V6 Dark Blue Wiper Motor Park
 
jhdeval said:
Is it possible the motor bogs down when ever it has to apply torque? Maybe something I can fix if so?
Click to expand...

YES There could be a bad bearing or worn gear that is causing the transmission to bind. Only way I know is to figure out how to get it apart and inspect it. And it could be something in the motor itself

So far as an ACC relay, you could put one, use the IGN switch ACC line to activate the relay, and run a good heavy no10 wire out to the start relay. Put a big fuse link, or auto reset breaker (you can parallel them) but keep away from engine heat the best you can. Heat degrades the ratings on either fuses or breakers

Use a GOOD heavy relay. When I had my old Landcruiser, I actually used a "continuous duty solenoid" for ALL switched loads. The wiring in that think "looked like hell" but there was NO voltage drop.

I could be wrong I hope someone else chimes in. It SEEMS that the 3 speed and variable motors are the same which would suggest that at least temporarily, you could sub a 3 speed switch. I AM NOT sure about this, so you might do some "Googlin'

Here's some stuff I hope helps you

These are screenshots out of my 67 manual so they may or may not be correct, but I've checked several years and all the variable stuff I can find over the years seems to be set up the same.

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Below is the screenshot of the 67 Dart switch. The wires go off the page and through the bulkhead connector

V1, going to B on the motor, is coming from UNFUSED switched accessory power directly from the IGN switch via the splice. There should be a breaker on/ in the wiper

The B1 wire, off the bottom B terminal is an OUTFEED feeding power OUT TO the backup light switch. The reason it is show this way on some diagrams is that earlier cars had the backup light switch on the swift mechanism, newer cars went out through the bulkhead and the switch was on the auto trans. All "stick" cars to my knowledge were also on the trans.

The rest of the wires, V3, V4, V5, V6 simply go through the bulkhead and connect with the motor

The exception is V10, hooked to W on the switch, which goes through the bulkhead, and hooks to the washer motor.

20st0mv.jpg


Below is a shot of the 67 Dart motor wiring. Just connect the wire numbers, which go through the bulkhead, to the same number above at the switch

wwdqp2.jpg
 
67Dart273 said:
YES There could be a bad bearing or worn gear that is causing the transmission to bind. Only way I know is to figure out how to get it apart and inspect it. And it could be something in the motor itself
Click to expand...

Do you know if parts are available? I have tried looking online and I have found several places that offer to rebuild it but specifically say they do not offer parts. I did notice at my local Ace Hardware they have some motor sweeps is it possible I may be able to fix it with out an original part?
 
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