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TR2/3/3A Wire and Wipers

TR3Novice

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This wire was cut off when my TR3B arrived. All pictures that I saw showed the wire soldered. I attached a connector and some additional wire and reconnected. My voltmeter showed that my Overdrive switch was wired backwards from everything I read (LHD Off is down with lettering facing me). Since I reconnected the wire the windshield wipers stop in the up position. When I disconnect I can stop them in the down position. First, is the wire part of the Overdrive? Second, how does it relate to the wipers, I realize the wire comes from the wiper blades motor I believe but not sure what’s up. If I leave it disconnected does that mean that the Overdrive will not function? Be kind, I’m new at this! Thanks, Donn.
 

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These wipers are curious beasts - and not wired in a manner that a normal person like me could ever come up with - nor remember. I suggest a search on the forum for "wipers", possible even with my username, and you should find the various writeups on their operations. Once reading how they work, and making a few sketches to confirm, it made sense to me. But quickly forgotten.

The wire connects to the circular bit. Basically, as the wipers go through their cycle, they rotate a contact, and when the contact reaches the "open" position the wiper stops. (I think the open position breaks the ground, and turning the wipers on connects them to ground - or perhaps I have this reversed?? Again, the wipers were designed by a clever electrical engineer!)

Rotating the round bit (loosen the four screws surrounding it) alters the stop position of the wipers.
 
That wire has nothing to do with the overdrive. It is strictly for parking the wipers, as Mike described.

The overdrive switch is just a toggle switch, right? If so, it should be no big deal to turn it around.

Do you have a wiring diagram for the car? Advance Auto wire has some nice ones, which they make available to everyone;
 
Thank you, just printed the diagrams. Before I repaired the wire I tested with the voltmeter from the wire fragment to the solder point. In one position on the Overdrive switch I had current and in the other position I did not. Does this make sense, that’s why I thought it was related to the overdrive and that the switch was wired backwards. Yes I can turn it to have the letters opposite me.
 
Sorry, I was wrong. Just tried it again and current is there in either overdrive switch position. Reconnected the wire and again the wipers stop in their upright position.
 
Thank you Tom. I found the same earlier and it worked out fine, the wipers work and finish correctly. Next step, not sure if the overdrive is functioning. Plenty of threads but a lot to learn for a newbie. I wanted to learn new things in retirement and the car has provided that. Something new to explore and learn everyday. Thanks again Tom, appreciate it!
Donn
 
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