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> Bench testing 1973 Intermittent Wiper, Confusion around wiper behavior
GeorgeKopf
post Jun 15 2025, 11:48 AM
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I'm bench testing my wiper motor without the intermittent wiper relay in the circuit.

1. Connect ground.
2. Apply power to red/white or red/black (53a)
(wipers park at the down position)
3. Apply power to black/blue (53)
(wipers run at the slow speed; when black/blue is disconnected the wipers park)
4. Apply power to black/purple (53b)
(wipers run at fast speed; when black/purple is disconnected the wipers park)
5. Apply power to green/white (31b)
(nothing happens)

Shouldn't this initiate one cycle of the wiper arms, after which they should park?
My understanding is that the wiper relay sends a periodic pulse through the green/white wire to trigger one cycle (one wipe).

If I apply power to red/white(53a), black/blue(53) and green/white(31b) and then remove the black/blue(53), leaving power to red/white(53a) and green/white(31b), the motor continues to run with a tiny pause where it would normally park. It seems that once it gets started the green/white(31b) prevents it from parking. If I remove power to the green/white(31b), the motor parks and cannot be restarted with just power to green/white(31b).

With the intermittent relay connected, the behavior is exactly the same, BUT I hear the relay chirp in between each cycle.

I'm hoping that my wiper motor is working correctly and that my relay is bad.

Am I testing this wrong?



Thanks.

George
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- Lo-Fi Version Time is now: 13th July 2025 - 06:23 AM