78 spider wiper woes

[MrBlimp]

I read James Seabolt's article https://www.mirafiori.com/faq/content/b ... hwiper.htm on wiper conversions. I "bench tested" to prove out the following (as per his article):
- Blue/Black --> Always hot when ignition switch is on
- Blue/White --> Hot only when wipers are in constant mode
- Black/Grey --> Hot on both slow and fast, constant and intermittent
- Blue --> Hot only on fast speed
- Grey --> Hot only on slow speed
- Black --> Ground

The only difference I found is that my notes show that "Blue/White --> Hot only when wipers are in constant mode" was hot all the time, BUT I need to test that one more time to make sure my notes are correct.

I don't think I was getting Ground from "Black --> Ground" so I ran my own (I found the same issue with the washer which worked fine once I ran a new ground. I am not sure where the ground wires on these two items connect to the car (I found where two black wires had made a ground under the dash on the glove box side that a PO had sniped - I wonder if that was the ground location).

The motor got hot so I opened the wiper motor to ensure nothing was jammed and it seems everything is fine - I added some lubrication to where the metal screw meshed with the plastic gear.

[spider2081]

Blue/Black --> Always hot when ignition switch is on
- Blue/White --> Hot only when wipers are in constant mode
- Black/Grey --> Hot on both slow and fast, constant and intermittent
- Blue --> Hot only on fast speed
- Grey --> Hot only on slow speed
- Black --> Ground

On my 1981 Spider that has the three 2 pin connectors:
Blue --- is hot in Slow speed only
Gray-- is hot in Fast speed only

The blue white wire and the grey/black wire are associated with park and delay switching. I would not be concerned with measuring voltage on them if your wipers are in-op.

First thing I do when servicing wipers is to make sure the linkage is totally free moving. Any stiffness in the movement of the linkage assembly will be a problem.
Power to operate the wiper motor in the constant speed modes is applied to either the blue or the gray wires of the motor. The ground completes the circuit.
The grounds for the wiper motor and the windshield washer are made at the grounding pod on the left front fender on my 81 not sure where the factory made your grounds. I would think as long as you provide a good secure ground on the black wire that should suffice

when connecting the 2 pin plugs match the wire colors in the plugs the plugs themselves could be different colors.

Hope this helps a little

[MrBlimp]

On my 1981 Spider that has the three 2 pin connectors:
Blue --- is hot in Slow speed only
Gray-- is hot in Fast speed only

My 78 has 6 wires - more to trouble shoot.

I would not be concerned with measuring voltage on them if your wipers are in-op.

The wipers (and a bunch of lights - which I already fixed - all ground issues cause by oxidation) weren't working hence the troubleshooting. Plus it proved that I am getting voltage at the motor so it proved that the switches and relays are all working.

First thing I do when servicing wipers is to make sure the linkage is totally free moving. Any stiffness in the movement of the linkage assembly will be a problem.

That will be final step - right now I have the motor out and am working on getting it to spin.

The ground completes the circuit.

I always follow Dwight's rule "It is always the ground" (I followed this on my LBCs as well, well before I knew to call it Dwight's rule. My rule has been "Cleaning the grounds fixes everything!"

The grounds for the wiper motor and the windshield washer are made at the grounding pod on the left front fender on my 81 not sure where the factory made your grounds.

I just removed both ground pods to clean them of the years of oxidation. The passenger side had only one wire attached. The Driver's side pod had three, none of which look like they are for the wiper/washer system.

I would think as long as you provide a good secure ground on the black wire that should suffice

I am hoping for the same - it definitely was the issue with the washer motor - as soon as I ran an independent ground wire to the ground pod it started to function.

when connecting the 2 pin plugs match the wire colors in the plugs the plugs themselves could be different colors.

Already verified and tested the connector is making a good connection by testing voltage before, after, and at the motor.

Hope this helps a little

Thanks, yes it did.