Wipers not working on 79 - Help Please
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 30
Likes: 1
From: Arnold Missouri
Wipers not working on 79 - Help Please
Added a C3 to my stable last weekend and am having some trouble getting the wipers to work. All I get is clicking from the relay in the dash while moving the switch down. The temperature guage also maxes out while the relay is clicking? When you press the switch all the way down to "Wash" I get one click from the wiper motor. The wiper motor is new and appears to be connected correctly. One red wire to the housing, one ground and the 3 pin connector. One post said to check the relay behind the a/c controls. Since it was only $12 I just decided to put a new one in. Still no wipers, only clicking. Can anyone help? I want to get this baby on the road but cannot pass Missouri Safety with no wipers.
Burning Brakes
Joined: Jun 2005
Posts: 764
Likes: 2
From: THE OLDER I GET THE BETTER I WAS! NORTHERN ONTARIO
C3 is brutal for ground check all your grounds related to the wipers assembly manual would be handy ... to have a gauge peg would mean that there is a bad ground someplace in the circuit.
Le Mans Master
Joined: Aug 2006
Posts: 7,425
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
There is a separate black ground wire on the wiper motor it should be connected to a starter bolt but it has a big lug and mistakenly gets hooked to the positive battery wire on the starter solenoid, check to make sure that wire is where it should be.
If that doesn't help go to Willcox (on the left) go to 1979, repair and install help and type in wiper. There are 2 repair guides, Corvette Wipers Switch and Corvette Wiper Test, Willcox is not posting tonight so try that until he returns. PG.
If that doesn't help go to Willcox (on the left) go to 1979, repair and install help and type in wiper. There are 2 repair guides, Corvette Wipers Switch and Corvette Wiper Test, Willcox is not posting tonight so try that until he returns. PG.
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 30
Likes: 1
From: Arnold Missouri
Thanks for everyones help. I did not see any type of controller in the jack compartment. It is basically an empty compartment with one vent tube on the bottom. Would this controller be in a different location in the 79? I will research all ideas, keep them coming.
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 30
Likes: 1
From: Arnold Missouri
Hey PG, I traced the ground from the wiper motor back to the passenger side of the block where it is spliced into a wire coming from somewhere in the front of the car. Will this cause issues? Does the wiper motor have to be grounded to the starter motor? I will visit the Willcox site as well. I already did their switch repair fix and cleaned all the contacts last week.
Le Mans Master
Joined: Aug 2006
Posts: 7,425
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
The wiper motor and the blower fan motor share the same ground wire.
Disconnect the ground wire on the wiper motor and try a jumper from that terminal to a good ground and test the wipers again. PG.
Disconnect the ground wire on the wiper motor and try a jumper from that terminal to a good ground and test the wipers again. PG.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Sorry the 79 controller is in the center console it wasn't until 80 they put it in the jack compartment.
Safety Car
Joined: Jun 2004
Posts: 4,371
Likes: 223
From: Beecher Illinois
The delay controller for 79 is located in the center console kinda under the radio. About 3" square with a bunch of wires coming out of it.
What relay did you swap? I can't recall any relay for the wipers, just the park relay that's built into the motor.
When you installed the new motor was the arm attached? You might try unbolting the arm from the motor shaft and try running it without the wipers attached. If the arm was installed 180 degrees off it would bind and the internal circuit breaker would prevent it from trying to run.
A new motor that was tested might not have returned to 'park'.
What relay did you swap? I can't recall any relay for the wipers, just the park relay that's built into the motor.
When you installed the new motor was the arm attached? You might try unbolting the arm from the motor shaft and try running it without the wipers attached. If the arm was installed 180 degrees off it would bind and the internal circuit breaker would prevent it from trying to run.
A new motor that was tested might not have returned to 'park'.
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 30
Likes: 1
From: Arnold Missouri
I replaced the relay on the firewall in the engine bay as well as the relay parked in the controller in the dash just to be safe.
I guess I should clarify, when i bought this car I knew the power locks, wiper motor and heater/ac blower was not working. It seems most of these items lead back to the controller where all the clicking is taking place. Is there any possibility this controller is to blame? I will take some pics of the device. On the back of the circuit board there seems to be some unusual matter. Maybe someone knows what it is? I have backtracked the ground on the wiper and I know that is good. I did not see another ground for the fan controls?
I guess I should clarify, when i bought this car I knew the power locks, wiper motor and heater/ac blower was not working. It seems most of these items lead back to the controller where all the clicking is taking place. Is there any possibility this controller is to blame? I will take some pics of the device. On the back of the circuit board there seems to be some unusual matter. Maybe someone knows what it is? I have backtracked the ground on the wiper and I know that is good. I did not see another ground for the fan controls?
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I always like to start these problems with verifying the motor first. Have you tested the motor function! http://willcoxcorvette.com/repairand...lp.php?hID=285
The controllers on the 1978-1979 cars were famous for failure! Dale Wilson... We'll Dale did the write up on our site about how to rebuild the switch and Dale is the man to see on fixing and testing your old controller.
I'm going out on a limb here it's been a very long time on the 79 for me. But if I remember right, didn't the controller harness plug in to the switch and then the normal wiper connector plug in to the back of this? Seems like I remember the controller failed on my 79 and I just un-plugged the controller harness and pluged up the stock harness to the switch. This gave me wipers but no pulse. You might check this and see. It might by-pass the controller and allow you to pass inspection.
Willcox
The controllers on the 1978-1979 cars were famous for failure! Dale Wilson... We'll Dale did the write up on our site about how to rebuild the switch and Dale is the man to see on fixing and testing your old controller.
I'm going out on a limb here it's been a very long time on the 79 for me. But if I remember right, didn't the controller harness plug in to the switch and then the normal wiper connector plug in to the back of this? Seems like I remember the controller failed on my 79 and I just un-plugged the controller harness and pluged up the stock harness to the switch. This gave me wipers but no pulse. You might check this and see. It might by-pass the controller and allow you to pass inspection.
Willcox
Last edited by Willcox Corvette; Sep 5, 2009 at 03:41 PM.
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 30
Likes: 1
From: Arnold Missouri
Here is the controller. Should the back of the circuit board have that orange matter between the solder points? 
, http://s706.photobucket.com/albums/w...e.jpg&newest=1, http://s706.photobucket.com/albums/w...e.jpg&newest=1
, http://s706.photobucket.com/albums/w...e.jpg&newest=1, http://s706.photobucket.com/albums/w...e.jpg&newest=1
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 30
Likes: 1
From: Arnold Missouri
Thanks Dale, I tried the jumper this morning. Now all i get is one click from the wiper motor when the switch is pushed all the way down to wash. I will test the voltage later this morning.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Last edited by ...Roger...; Sep 6, 2009 at 02:11 PM.