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2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Pics are from floor looking up. Not great but its visible. The harness is clearly not long enough to make it to the top of the speedometer
The tape id coming off the fiber optics but you can see the harness behind it
Brass long nut is the speedo trip reset. The wedge is the top of the column
Steering column on left
Steering column on right. You can see the harness and optics above the tach cable. The spliced wiring is a ground that I had to extend but needed it removable
Coming out of steering coumn going above the tach cable
Last edited by Rescue Rogers; Oct 1, 2016 at 09:34 PM.
Hi, just an update on the project. So, I installed the new solenoid and it isn't working. Also, noticed the previous owner removed the filter from the vacuum source.
Is it common to get a bad part like the solenoid? Wiper door opens fine when I bypass the solenoid. i.e. hook it back the way the previous owner set it up.
Have you verified that 12vdc is being sent to the solenoid by the wiper switch when it is turned ON? It could be a problem with the wiper switch, its wiring, or that power is not even getting to the wiper switch.
P.S. I have seen that the wiper switch CAN be installed upside down...in which case it will not operate correctly. Check the drawing in the AIM to assure that it is assembled correctly.
Mine had been working wonderfully for years and then yesterday I went to take a drive after a couple of weeks of not using the car.... well, the battery was dead. I removed the battery and slow-charged it overnight.
Today i went out there and installed the battery...as I was hooking it up I heard "something" pick up. Turned out to be the wiper solenoid that sits under the dash.
NOW I have to figure out why it was being energized while the car is turned off.
Any quick pointers before I dive into troubleshooting?
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Check the overide switch under the dash. I know on a 68 it provides a ground to my system that trips the solenoid to release the vacuum, or something. My switch will drain my battery if left on. I put a dot of white paint on it so I can tell its position easily.
Meanwhile, per the wilcox guide above, the wiper solenoid on a 68 is sitting there grounded and waiting for 12 vdc from the BROWN wire when the wiper motor is running. Well, my wiper motor is NOT running and obviously mine has 12 vdc on the BROWN wire at all times so I have to go figure out why.... ?????
Originally Posted by Rescue Rogers
Check the overide switch under the dash. I know on a 68 it provides a ground to my system that trips the solenoid to release the vacuum, or something. My switch will drain my battery if left on. I put a dot of white paint on it so I can tell its position easily.
Here is the text from that link above concerning the wiper solenoid; note that on the 1968 the ground is constant and it is sitting there waiting for 12 vdc from the wiper motor running:
I understood that the 1968 was a bit different, but since mine has mostly worked well I had not investigated. Many thanks to Wilcox.
Now I have to go figure out why mine decided to be energized.
To answer your question:
YES- the car started fine.
NO- the wipers are not working.
Originally Posted by Rescue Rogers
Ive read its the exact opposite. Always has 12 vdc waiting for ground. I've been known to be wrong before so Im not surprised if I am.
Since your battery is fresh, did it start and do the wipers work?
Last edited by carriljc; Oct 15, 2016 at 11:54 AM.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Yes I did get that part backwards, thanks. So what exactly isnt working, the door not openning or the wipers not wiping? There is a trouble shooting addendum in the aim to help diagnose which part has failed. Willcox might have that posted as well
I will start the troubleshooting this upcoming week...
Thanks for the pointers.
My initial investigation was to just find out why I had constant current draw from the battery.
I really have to go find out why the power lead to the wiper door solenoid has power when it should not. Doesn't sound too terrible.
I did manage to redraw that vacuum diagram so that it makes sense to me and get a better understanding of how the system works.
I have a vacuum pump so I should be able to do some troubleshooting without running the engine.
I only started the engine to ensure it started. I did not try to run the wipers with the car in the garage....gets mighty exhaust stinky pretty fast. Of course neither the wiper door nor the wipers worked later with just the key in ON (should have had some residual vacuum), but I did not investigate further. Just put it away with the wiper door solenoid, and battery, disconnected.
Originally Posted by Rescue Rogers
Yes I did get that part backwards, thanks. So what exactly isnt working, the door not openning or the wipers not wiping? There is a trouble shooting addendum in the aim to help diagnose which part has failed. Willcox might have that posted as well
Last edited by carriljc; Oct 16, 2016 at 10:42 AM.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I have a vacuum pump that works off an air compressor. It was pretty cheap. I may invest in an electric one from harbor freight. They run the $100.00 but should be on sale or available with the discount coupons.
More genius headaches for 68 owners from the GM gods.