Another wiper switch question...1965 New Yorker

[Raxxter]

The windshield wipers on my New Yorker have stopped working completely. They’ve never worked right; the best I’d get since I’ve owned the car would be a couple of cycles before they would stop wiping, although the motor would continue to make the odd groan or knock.

In a related issue, the reverse lights would sometimes work, but most often wouldn’t. When they would work, they tended to flicker a bit and then go out.

I decided to try and fix the wipers, as I’ve been stuck driving it to work only when the weather calls for clear skies.

Looking at the wiring diagram, I discovered the windshield wiper switch and the backup lamp switch are wired together. I figured I’d pull the wiper switch to inspect it and clean it, hoping I might be able to find or correct the wiper and the reverse light faults. After pulling, cleaning, and inspecting the switch, I didn’t find anything obviously damaged or out of place. The switch and wiring seemed in pretty good condition.

I should note, it’s the rheostat-equipped switch (is this the “3-speed” switch vs. the “2-speed” switch? I’m not sure…), and an automatic transmission with the reverse light switch on the column.


My situation is this:

The wiper switch B terminal and the B/U (? - terminal that connects to the B1 circuit white wire that runs to the backup switch) terminal ‘ohm out’ with no resistance between the terminals through the switch, no matter which position the switch is in.


I get 12 volts (ok, about 11.4-ish) at the pink V1 wire that plugs into terminal B on the back of the switch. I get the same voltage at the B terminal blade when the V1 wire is plugged in.


I don’t get any voltage at the B/U terminal when there is voltage present at the B terminal.


My question is:

What is the likely cause of not finding any voltage at the B/U terminal, if there is voltage present at the B terminal, and the B - B/U terminals ohm out?

Is the voltage likely grounding out somewhere in the switch itself? How would I test this?


If anyone has come across something like this, or has dealt with a similar issue and can provide any guidance, I’d appreciate it.


(I’ll see if I can get some pictures up later today….pictures always help, I believe)

 

[Ross Wooldridge]

The rheostat version is variable speed wipers... slow, fast and variable in between...

Make sure you have the car in reverse (engine off, wheel chocked or parking brake on, key in run position) to get power to the switch, as the circuit is closed only when the backup lamp switch on the column or console is engaged.

The wiper harness and B/U lamps use the top connector on the bulkhead in the firewall - check and clean that area as it is often the source of poor and intermittent connections. While you're at it do the same for the remaining two connectors. You might be surprised and alarmed at what you find.

As well, the wiper motor grounds through a brass ring to the cowl, and I think the B/U lamps ground to the bumper. Check both those.

 

[Raxxter]

Ross, thank you for your response.

I should have noted that I have confirmed the reverse light switch by verifying a closed circuit with a multimeter by the exact method you recommended (key in run position, engine off, wheels chocked, shifter in reverse). The circuit closes very well when I have shifted into Park - no wiggling, or bumping of the shifter required to close the circuit and keep it closed. The circuit is open in all other positions.

I also verified the white wire, B1, from the reverse light switch to the wiper switch is good. Later today I’ll jump 12 volts to the wiper switch end of the B1 wire, so I can check the reverse lights all the way to the bulb.
I’ll inspect, and clean, the bulkhead connectors today, as well as check the grounds.

Would a bad ground account for the 12 volts present at the B terminal (when the key’s in the ‘run’ position) not making its way through the switch to the B/U terminal, even when the path ohms out?..

I’ve just plugged in the camera battery, so I should be able to post pictures later today, too.

 

[Ross Wooldridge]

Remember that "closed" means power is able to flow and "open" means a break somewhere either a switch or a true break.

If you have a closed circuit in park, then your reverse switch is likely out of position and needs to be positioned so that ot's open in Park, N, Drive L1 2 3 and closed ONLY in reverse.

Yes, bad grounds are a big source of electrical gremlins!

 

[Raxxter]

I misspoke.
The circuit is, in fact, closed in Reverse (power flows through the circuit), not in Park.
Don't know what I was thinking.

 

[Ross Wooldridge]

Lol... no worries! Check those grounds and bulkhead.

 

[Davea Lux]

Sometimes, when there is intermittent operation of the wipers, it is because the brushes in the wiper motor are worn out and not making good contact. Have you rebuilt/replaced the wiper motor?

Dave

 

[live4theking]

To answer your question of could it be grounded out and still ohm good, yes.

If the wire is grounded out, but not broke completely. try ohm test to ground to rule this out. Power could possibly go to ground instead of through the wire if that is a better connection.