Wiper Override Help!!!
Thread Starter
Advanced
Joined: Oct 2004
Posts: 62
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From: Bowling Green KY
Wiper Override Help!!!
Im working on a 68 BB car and need some help. I took the dash out of it and had the mechanical tach converted to electric. I put the dash back in the car and the next day the battery was dead. I knew then that it must have a voltage drain somewhere. After doing some checking, I found that as soon as the battery cable is connected (ignition off or on, it didn’t matter) the wiper override solenoid is activating. I pulled the gauge cluster back out to make sure I didn’t miss anything when I reinstalled it, and I didn’t. A little history about the car: My granddad bought it new in 68 and it was originally a small block car that was later converted to big block. About 5 years after he bought it it was stolen and a lot of the parts were stripped out of the car before it was left sitting on the side of the road. A lot of the dash was torn up, but from what I can tell none of the wires were cut.
I don’t know if something happened when it was stripped, or if there is some common problem that I don’t know about. Thanks for any input you might have!!!
I don’t know if something happened when it was stripped, or if there is some common problem that I don’t know about. Thanks for any input you might have!!!
Burning Brakes
Joined: Sep 2005
Posts: 1,044
Likes: 33
68 wiper problems
Originally Posted by 68 Blues
Im working on a 68 BB car and need some help. I took the dash out of it and had the mechanical tach converted to electric. I put the dash back in the car and the next day the battery was dead. I knew then that it must have a voltage drain somewhere. After doing some checking, I found that as soon as the battery cable is connected (ignition off or on, it didn’t matter) the wiper override solenoid is activating. I pulled the gauge cluster back out to make sure I didn’t miss anything when I reinstalled it, and I didn’t. A little history about the car: My granddad bought it new in 68 and it was originally a small block car that was later converted to big block. About 5 years after he bought it it was stolen and a lot of the parts were stripped out of the car before it was left sitting on the side of the road. A lot of the dash was torn up, but from what I can tell none of the wires were cut.
I don’t know if something happened when it was stripped, or if there is some common problem that I don’t know about. Thanks for any input you might have!!!
I don’t know if something happened when it was stripped, or if there is some common problem that I don’t know about. Thanks for any input you might have!!!
Burning Brakes
Joined: Sep 2005
Posts: 1,044
Likes: 33
Originally Posted by 68 Blues
Im working on a 68 BB car and need some help. I took the dash out of it and had the mechanical tach converted to electric. I put the dash back in the car and the next day the battery was dead. I knew then that it must have a voltage drain somewhere. After doing some checking, I found that as soon as the battery cable is connected (ignition off or on, it didn’t matter) the wiper override solenoid is activating. I pulled the gauge cluster back out to make sure I didn’t miss anything when I reinstalled it, and I didn’t. A little history about the car: My granddad bought it new in 68 and it was originally a small block car that was later converted to big block. About 5 years after he bought it it was stolen and a lot of the parts were stripped out of the car before it was left sitting on the side of the road. A lot of the dash was torn up, but from what I can tell none of the wires were cut.
I don’t know if something happened when it was stripped, or if there is some common problem that I don’t know about. Thanks for any input you might have!!!
I don’t know if something happened when it was stripped, or if there is some common problem that I don’t know about. Thanks for any input you might have!!!
Thread Starter
Advanced
Joined: Oct 2004
Posts: 62
Likes: 0
From: Bowling Green KY
The part I am referring to is mounted to the back of the tach. It has two vacuum lines connected to it and a two wire flat plug. In my case the wires are brown and black that connect to it. I will get a wiring diagram, maybe I am calling this the wrong thing????
Heel & Toe
Joined: May 2006
Posts: 19
Likes: 0
The tach solenoid should have two double wires running to it. A Double blue and a Double Yellow. The Blue wire runs from the Wiper motor connection to the solenoid. Then from the solenoid to the wiper switch, and then to the wiper motor relay. The yellow wire runs from the Center connection of the wiper motor, then to the solenoid, and then to the wiper motor relay.
All the solenoid is there for is to break the wire connection in case the wiper door is not open. The vacuum that feeds the soleniod comes from the wipre door arm switch under the cowl door.
I doubt this is your drain.
Have you tried to narrow the drain down? You can do this by testing the battery without the cables hooked up. See how many volts are in it. Then hook up the battery and see the volts in it. The difference is your draw.
Go to the fuse panel, pull a fuse and take a battery reading. Compare this to your draw. Do this one at a time and you will find out what draw is on what circuit.
It narrows it down for you.
All the solenoid is there for is to break the wire connection in case the wiper door is not open. The vacuum that feeds the soleniod comes from the wipre door arm switch under the cowl door.
I doubt this is your drain.
Have you tried to narrow the drain down? You can do this by testing the battery without the cables hooked up. See how many volts are in it. Then hook up the battery and see the volts in it. The difference is your draw.
Go to the fuse panel, pull a fuse and take a battery reading. Compare this to your draw. Do this one at a time and you will find out what draw is on what circuit.
It narrows it down for you.
Thread Starter
Advanced
Joined: Oct 2004
Posts: 62
Likes: 0
From: Bowling Green KY
I tracked the drain down by unhooking the ground cable on the battery and using a remote starter switch between the ground cable and the ground post on the battery. When ever the connection is made, this solenoid clicks immediately as if it has engaged. This is most definately the drain, with it unhooked it doesn't drain the battery. There are only two single wires going to this, one brown and one black.
Thanks!
Thanks!
Instructor
Joined: Nov 2003
Posts: 106
Likes: 1
From: Indiana
Burning Brakes
Joined: Sep 2005
Posts: 1,044
Likes: 33
68 Wiper System
Here's the sequence:
Turn wiper switch on
- Electric Vacuum relay [attached to back of Tach] engages and enables vacuum to wiper door system <<-- this could have issues from what you describe
- Wiper door opens
- When door is fully open, microswitch closes
- Wipers come on
Turn switch off
- Wipers park [and contact vacuum switch in passenger side cowl well]
- When wipers are fully parked and above vacuum switch is FULLY pressed, vacuum is enabled to wiper door actuator
- Microswitch OPENS disabling the wiper motor
- Wiper door closes
Make sure the ground to the wiper motor is solid - this can also intermittently prevent the wipers from coming on (but the door WILL open).
I saw this a wile back and may help, AL
Turn wiper switch on
- Electric Vacuum relay [attached to back of Tach] engages and enables vacuum to wiper door system <<-- this could have issues from what you describe
- Wiper door opens
- When door is fully open, microswitch closes
- Wipers come on
Turn switch off
- Wipers park [and contact vacuum switch in passenger side cowl well]
- When wipers are fully parked and above vacuum switch is FULLY pressed, vacuum is enabled to wiper door actuator
- Microswitch OPENS disabling the wiper motor
- Wiper door closes
Make sure the ground to the wiper motor is solid - this can also intermittently prevent the wipers from coming on (but the door WILL open).
I saw this a wile back and may help, AL
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Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Also you should have a wiper service override switch under the dash that will stop the wipers on the windshield. The owners manual states: CAUTION: Never leave the override switch in the "On" position since this will discharge the battery.
Yes, Chevy actually designed a battery drain into the car!
Yes, Chevy actually designed a battery drain into the car!
Intermediate
Joined: Jun 2006
Posts: 38
Likes: 0
From: MA
I have a 68 and a question... where is the 'microswitch' supposed to be, the one that the wiper door moves, and when switched it tells the wipers to go? The door opens fine for me but the wipers won't move.
Also another dumb question, but of the two switches under the dash, which one is the wiper overide? the one on the right I can turn, and the one on the left i can push... I just got the car, and never went over it with my father... Also, is the high beams the other switch under there? how do i turn those on?
Also another dumb question, but of the two switches under the dash, which one is the wiper overide? the one on the right I can turn, and the one on the left i can push... I just got the car, and never went over it with my father... Also, is the high beams the other switch under there? how do i turn those on?
Burning Brakes
Joined: Sep 2005
Posts: 1,044
Likes: 33
Originally Posted by Lucky68
I have a 68 and a question... where is the 'microswitch' supposed to be, the one that the wiper door moves, and when switched it tells the wipers to go? The door opens fine for me but the wipers won't move.
Also another dumb question, but of the two switches under the dash, which one is the wiper overide? the one on the right I can turn, and the one on the left i can push... I just got the car, and never went over it with my father... Also, is the high beams the other switch under there? how do i turn those on?
Also another dumb question, but of the two switches under the dash, which one is the wiper overide? the one on the right I can turn, and the one on the left i can push... I just got the car, and never went over it with my father... Also, is the high beams the other switch under there? how do i turn those on?
