File this one under nothing's ever easy!

Thought I was going to be successful on my first try doing this, what I overlooked was not doing the wiper high speed check when I was attempting to find out if the wipers would work at all. Steering column switch ('77) does nothing, so I had simply jumpered the wires at the wiper connector on the firewall. Voila! Low speed anyhow, putting wire across high speed to low speed connections (no ground wire needed).

Bought a marine 3-way switch (Attwood) since it seemed to have all the prongs I would need for the wires to connect how I needed them to be.

Ground (from washer motor ground on wiper housing, I guess) goes to a corner brass-colored prong, light blue (or dark blue bypass) high speed wire onto center silver-colored prong and black (or green bypass) low speed onto opposite end of ground prong side.

Have a look at the pictures, please.



Rereading after posting, guess I should mention the prong between ground and center (blue) isn't used here. Tried moving blue wire there already, and connecting blue across both that one and center. Only difference is light for that side shows up when On position is used, if other prong is not used, no light. Only the other for low speed (green) wire. {BTW, I know high+low=low, and ground+high=high.. um, right??}. And... there's a plastic rod sticking out between blue and green at right side, not another prong there. Just the 4 total.


I'm going to put the switch into the ashtray eventually, so ignore the mess of wires except where they connect on switch and wiper connector.



Was going to use the vacuum hose grommet in the firewall, you can see the pair of hoses into it. Realized there was a more convenient place just below it and above the accelerator pedal inside the car.

That rubber plug/grommet wasn't going to pull or push out for me so I simply cut off the cone-shaped end at the outside firewall. Found it had a hole big enough to fit three 16 gauge wires through, so that was lucky.
Picture shows it being tried with ground (another green) wire insulation removed on both ends so I would know which it was while installing the switch. Black tape or black marker pen was another idea for that but didn't need to do it.

So... back to why I said nothing's easy.
Not only did the high speed not work but when I closed the hood for a final test (of low speed only), the wipers started to move and stopped!

I figured the fuse had blown. There was a 30 Amp in the fuse panel before, because I didn't have a 25 Amp until I bought some. Now with the 25 Amp in there I thought maybe the reason the wipers stopped was the 25 Amp not being able to handle the power like it's supposed to.

Well, wrong. It was actually the hood itself. Long story short, a couple months ago I noticed the hood would latch loosely and then if pushing down harder directly over the latches it could be tighter. Latches a second time and hood is firmly in place that way, although not lined up with fenders as well.

That was why. Passenger side wiper has some sort of bracket piece atop the arm and it was catching on the edge of the hood. Removed latch hooks from hood itself and added washers, believing that was be enough to clear. Nope. Not if double latching tightly, but first catch and loose was okay now.

If any of you reading here got this far and have any ideas about the high speed not working with my switch setup, or whatever else might be the reason for the lack of high speed, I really appreciate all advice your able to give me.
Confounded me trying to understand it, thinking might be as simple as a constant contact of low & high speed wires someplace (steering column switch).

Maybe all this will also give someone else hope for getting wipers to work again if you're without them in the rain like I was.

 

I BELIEVE this is your problem. The switch is not able to do what the motor needs to work correctly.

OK...do you KNOW how the wipers work??? THAT is critical. Because IF you do not understand HOW GM gets the wiper motor to work....then using a switch that can not do what is needed will make you go crazy.

'Bench testing' your wiper motor is EASY...and it can still be in the car.

DO you know how to do this or HAVE you done this???? If you have not....you need to ..because THEN you will understand that all GM is doing is changing the grounds going to the OUTER two terminals of the connector ON the motor.

The wiper motor MUST be grounded....this is a MUST!!!!

The CENTER terminal in the 3 wire connector is your battery power WHEN the key is ON. THIS DOES NOT CHANGE. Because...it is the combinations of ground and lack of ground ON the OUTER two terminals that gives you the three modes of operation....PARK....LOW speed...and HIGH Speed.

Willcox has a bench test outline you can follow. It is really simple when you finally figure it out....and that is WHY I mentioned I doubt that the switch you have will do what you need.

DUB

 

Thanks, yeah, I must confess I only went over the wiper motor bench test stuff (watched video, not actually doing anything) a while before I tried the first check and found out the motor still runs okay. Didn't go step by step and that's obviously what I should have done.

I will give it another go tomorrow to find out if high speed does anything directly at the motor connector without the switch.

I'm going to give the testing procedure a look again right before I try that, too. I was going by memory this time.

What I was thinking could definitely be a problem, before attempting any of this, is how the testing video I had seen was telling about the switch needing to go from low to high and back to low then off for the wipers to park.
Thing is, that hasn't been any trouble yet other than no high speed. They always park and start up perfectly okay. Just no high speed when using the new 3-way rocker switch.

I might be mistaking how I miss that high speed, because of course it'll park the wipers from low every time according to the helpful video. At least guessing so.

Anyway... I've got to check without that switch, like you said. Maybe all is not lost-- rather high speed not lost-- until I can be sure what's happening with that.

 

Here's what the wires need to see the operate the wiper motor.

The red wire will NOT be on you 77- it's on the 68-72.

 

Hmmmmm. Okay.

Here's something about that switch I was trying to use. Before giving up on it I had moved the grounding wire (connected at washer ground) from the switch ground terminal/prong to the opposite side from low speed wire, leaving blue high speed wire on center terminal/prong, so I expected that to work right.

If all it needs for high speed is grounding the high speed wire connector at the motor I couldn't understand why nothing happened, since that's what it does. However, a lot depends on what's going on inside that switch and I don't really know, it's only a guess.
Oh, nevermind... forgetting again it goes off-low-high-low-off. Instant high speed might not be possible, you think?

Like I said before, I'm going to need to check that at the connector later to leave the switch out of the loop. I should have done that at the very first but I was just wanting low speed wipers for the drive to a car show I went to Saturday. Almost needed them, too, but I would have had to do the wire jump under the hood for that.

 

If you have a ground on the case of the wiper motor- power at the yellow wire and blue wire to ground- that'll be high speed.

If that works- then we need to see the specifics of the switch. If it doesn't- a bad wiper motor- or a solenoid more than likely.

Without knowing the specifics on the switch you are using- the motor might be seeing a ground through the switch to the green wire...

I modded a stock motor to operate w/ a newer GM Caddy delay/intermittent- and I handled the high & low grounding w/ a shunt by using a couple of relays.

Richard

 

Thanks Richard. I ended up with this switch because all others had only 3 connectors, or a metal toggle switch with 6. Unfortunately all I know about it is the ground being at one corner, positive center and other 2 each side for whatever is to be switched on (center is Off).

I did the test for both high speed and low speed the right way this morning, nothing wrong with the motor.

The way I had figured it, without knowing the switch circuit inside, was to use the ground as ground. High speed as positive. Low on opposite side of where ground is at.

High speed should use the ground when switched On for its side but I was going to leave the other connector open. Probably not correct but I also tried it with the high speed wire on both center and end (next to ground) opposite the low.

I've been thinking the problem could be how the switch is a lighted one, meaning power must go to both sides/ends when they are On. However I can't imagine the low speed could be constantly in the circuit since it only goes to the isolated (supposedly) connector for 2nd switch operation.

Uh, brainstorm... maybe ground is across both terminals even when Off. That would keep low wire in the circuit when high is On.

Problem then is to isolate high and still be able to connect with low.

I will be trying more today.

 

Something I wasn't aware of until now, what I thought was low speed all this time was really the high speed.

Apparently there is a short in the steering column switch causing the low speed to always contact the high speed or their ground.

Didn't have a reference point before. So with high speed confirmed with all else disconnected I was able to see the very low, low speed mode. Surprised me because I was thinking high speed would be throwing those wiper blades around on the windshield, not just leisurely sweeping back and forth.

Maybe the motor is tired, or that's the way it is for these cars.

Onward to the switch... nothing I tried would enable both low and high speeds using the rocker switch itself. I was only successful by short-circuiting across a couple connectors, directly touching high and low wires together.

Remember that this is after disconnecting the steering column wires to get that other switch out of the loop.

Well, now I'm considering going with two switches wired across each other. If that'll be okay. Otherwise I need to find another kind of single switch capable of doing this, maybe the 6 terminal kind of 3-way...?

Thanks for the help so far. Don't feel obligated to try anymore but if anyone happens to know of a proper switch, other than replacement column type, I would be grateful to hear about it. Likewise anybody else doing same might, too.

 

It is wise to remove the linkage from the backside of your wiper motor do you are not DRY WIPING your wiper blades on your windshield. OR...have a spray water bottle and keep your windshield WET when doing this. It does make a difference.

SO..I am stepping out on a limb here. But I assume you have understood HOW your wiper motor works...and actually tested the way it needs to work...by removing the facotry 3 wire connector and verify how the GROUNDS SWITCH when you use your switch on the steering column????

AS for a 'proper switch'.....you can use the wiper switch for an earlier year ..and wire it in accordingly. The wiper motors all operate the SAME....in regards to the switching of the grounds on the outer terminals of the 3 wire connector.

DUB

 

Been watering the wipers and windshield before turning them on, yes. New blades on there so didn't want to damage them. Also oiled all moving parts and pivot points in wiper linkages. No telling how long this car didn't have working wipers but looked like years and years.

I didn't have anything to go on for checking the column switch itself but the motor checks out okay alright. Guess I could have looked for continuity using my DMM to try and find out where it failed, wires or switch itself, but I wasn't thinking of fixing that anyhow.

Column work will have to wait... and wait.

Good idea about using a previous model year wiper switch, that would probably fit well in the ashtray. And looking at those for sale online after seeing $20 to $30+ for those I just now found a wiper switch that looks like this marine one I already have. With a difference. Other is a wiper specific switch and says it's On-On-On for a Park, Low and High. Almost half the price and looks good too.

http://store.amequipment.com/rocker-...tor-p-119.html



Wiring for that switch. Doesn't look possible to me. Not same type? Or does this look like it could be done by skipping the red battery wire? Guess there isn't a way to know for sure unless tried.

 

Here you go-

Yep, it'll work.

 

I do not know how you figured that out..I could not find their schematic on how the internal portion of the switch looked. GLAD you figured it out.

DUB