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New Group Created - Two (2) speed Lucas wiper motor wiring

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Spiker

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Spiker has created a new group called Two (2) spped Lucas wiper motor wiring.

Lucas wiper motor wiring pictures,06,02,26

I have tried this wiring too many times.
What I don't understand is that in a bench top test using a "Jump Starter/Power Pack", the wiper has a stop position, a speed 1 position and a speed two position. It works as I would expect it to.
When I hook it up in the car following the exact same circuit and "Jump Starter/Power Pack", it blows the inline fuse I have in the power line.
I have confirmed the each wire is hooked up exactly as it was in the bench test.
I've attached some pictures of the bench test set-up which worked.
Any thoughts on where I'm going wrong?
 
I feel like the simple andwer is that either something is grounding in the car wiring or there is too much of a current draw.

1. what is the amperage of the inline fuse? A quick google suggests that there can be quite a high draw. Seems like the manual wants a 35 amp (British amps) fuse.


2. if a short - it should happen regardless of draw. Could you wire a horn or lightbulb in its place and see if that blows the fuse also.

good luck!
 
Thanks for your response JP. I have the inline fuse in place during the bench test (NOTE: motor is in the car and hooked up to the wiper cable) with a 15 AMP fuse. Once I hook the wires that I've installed to connect the motor to the switch, when I activate the Power Pack and the switch is in the off position, the fuse blows. I have labeled the wires to ensure I have connected them the same as the "Bench test set-up" and yet, the fuse blows upon activation of the power source. I even tried grounding the case of the motor to no avail.
it's driving me nuts!
Spiker
 
If you have a Lucas 14W wiper motor, it requires a very special switch. I don't believe there is a practical way to make it work with any "standard" sort of switch without a relay involved. It grounds back through the switch as I recall. Anyway, if the motor is not in the park position, it will draw current for low speed trying to park itself. So it can blow a fuse even with the switch in the off position. I have more info if you need it.
 
DR3A Wiper Motor,06,03,26.jpg
 
I don't now about the DR3A. My Prefect has a 14W and the Sprite is single speed, DR2, I think. But I would bet the comment about the self parking function still applies It can be hot with the switch set to off.
 
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