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Electrical short - I'm not sure where to look

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Rollin's65

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Maybe someone has seen this.
I know another electrical problem. Sorry, but I really could use a pointer in the right direction.
With the ign switch in the off position. No problem
Switch to either the on or the acc, I've got a short.
I pulled all the fuses and the problem is still there. None in the fuse block.
There is a large 12 pin connector under the dash forward of the fuse panel that when I separate, the problem goes away. This is not attached to the fire wall. Probably in and out of the fuse block.
I'm assuming that the acc position doesn't connect anything through the two firewall connectors except for the wiper motor connections on a separate wire set
I'm in need to know which circuits are unfused from the acc position if anyone might know.

Boy would I like to start my 65 with it's new engine. REALLY!!

Thanks ahead of time -- Rollin
 

IH2LOSE

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1966,and a 1962 thats almost complete
I think the connector your describing is the connector that goes to the rear of the car,

fuel gauge ??
dome light (Fused)
antena (fused)
rh tail and stop & directional (Fused)
lh tail and stop & directional (fused)
Back up lamps ?( Fused)
And I think on a 65 a rear blower motor ?????


I would think the only thing on a non fused circut would be the fuel gauge
I would see if some one has a wiring diagram for a coupe and find the 3 wire colors for the fuel gauge and disconect the wires from the connector to confirm if thats the problem.

Did you do any thing with the fuel tank or near the wires for the fuel tank?

Best of luck
 
Joined
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1965 Coupe L76 / 1978 L82
ok, I tried to help by looking at my '65 wiring diagramn form Don Olsen but it doesn't seem to be telling me much to help;

The fuel gauge only shows TWO wires, not three as Larry mentions.
one is a Pink/black wire
the other looks to be a gold or mustard type color wire.

tracing those two wires:

the pink/black wire runs and connects to 4 other wires: these than go to the following areas:
1. one wire runs to a connector on the firewall than continues to a back-up lamp switch
2, another wire runs to the fuse box
3. another wire runs to the temp gauge
4. another wire runs to parking brake warning light

the gold/mustardish color wire goes to a connector:
the associating side of the connector is a yellow/black wire which goes to the ign. switch

NEXT:

theere is another item marked fuel gauge with THREE wires shown in the back of the car that i'll assume is really the fuel gauge SENDER unit:

the three wires coming from that are:
Black
Pink/black
gold/mustardish color

they go as follows:
1. black wire: - goes to a common ground junction along with wires from a body electrial connector, heater blower motor, tail lights, back-up light, license plate light
2. Pink/black wire: runs to a connector (same one mentioned above that also goes to the common ground junction for the black wire). the other sid of the connector shows a Orange/black wire that than runs to both the rear compartment light and the dome light.
3. gold/Mustardish color wire: runs to the same connector. Other side of the connector is a yellow/black wire that runs to rear taillight/blinker light.

See, this makes NO sense at all. this doesn't even show the fuel sender unit connecting to the fuel gauge itself. something is completely screwed up here trying to trace these wires!
 
Joined
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www.67HEAVEN.com
Barry,

The 20P (pink) traces back from the common point, through the body connector, to the sending unit. In other words, 18P to the common point, then 20P back through the body connector, along with the 18T, to the sending unit.
 
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1965 Coupe L76 / 1978 L82
67HEAVEN said:
Barry,

The 20P (pink) traces back from the common point, through the body connector, to the sending unit. In other words, 18P to the common point, then 20P back through the body connector, along with the 18T, to the sending unit.

ummmm, ok, if you say so, i'll take your word for it.
darn if I can see it though.
 

Vetsvette2002

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Willowbrook, IL
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67 convt. L79 Marina Blue
Barry

The gauge on the dash only has two wires. The meter or sending unit at the fuel tank has the three wires.:beer

Don OlsOn :)
 
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1965 Coupe L76 / 1978 L82
Vetsvette2002 said:
Barry

The gauge on the dash only has two wires. The meter or sending unit at the fuel tank has the three wires.:beer

Don OlsOn :)

yep, i figured that - your chart lists both as "gage" though but figured the 3-wire was the sending unit.

sorry I misspelled you name
 

IH2LOSE

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Vetsvette2002 said:
Barry

The gauge on the dash only has two wires. The meter or sending unit at the fuel tank has the three wires.:beer

Don OlsOn :)

I have heard great things of your wiring diagrams, Keep up the great work sir, Any words of wisdom on this problem this fellow has?
 

magicv8

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Going too fast over the hill.
I posted a wiring diagram for a 66 A-C c2 on the bottom of a web page at
http://www.corvetteforum.net/classics/magicmachine/index5.shtml

If you look at it, you see that all pink and brown wires are powered by the key switch and are unprotected by fuses in a factory correct car.

The brown wires are the only ones powered in both the ACC and IGN positions. On the diagram you see that brown wires leading to 2 plugs on the wiper motor, the flasher plug, a line to the fuse box and a line to the bulkhead plug are the probable problem sources.

Let me know what you find.

PS: I can email you a 65 A-C coupe diagram if you need one, but IMO except for the rear blower, it is the same as the 66 A-C diagram.

PPS: Since all the fuses are out, I suggest disconnecting the wiper plugs first, then the flasher, then the voltage regulator. If the problem persists, IMO the main dash harness has been damaged or possibly modified by a previous owner.
 

Vetsvette2002

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Messages
198
Location
Willowbrook, IL
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67 convt. L79 Marina Blue
Rollin's65 said:
Maybe someone has seen this.
I know another electrical problem. Sorry, but I really could use a pointer in the right direction.
With the ign switch in the off position. No problem
Switch to either the on or the acc, I've got a short.
I pulled all the fuses and the problem is still there. None in the fuse block.
There is a large 12 pin connector under the dash forward of the fuse panel that when I separate, the problem goes away. This is not attached to the fire wall. Probably in and out of the fuse block.
I'm assuming that the acc position doesn't connect anything through the two firewall connectors except for the wiper motor connections on a separate wire set
I'm in need to know which circuits are unfused from the acc position if anyone might know.

Boy would I like to start my 65 with it's new engine. REALLY!!

Thanks ahead of time -- Rollin

Why do you say you have a 'short'? Are you blowing a fuse? Which one? What are your symtoms of this short?

The connector you mentioned is the Rear Main Harness connector (IF it is near where your left knee is when you sit in the drivers seat).

Don
 

Vetsvette2002

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Joined
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Messages
198
Location
Willowbrook, IL
Corvette
67 convt. L79 Marina Blue
BarryK said:
yep, i figured that - your chart lists both as "gage" though but figured the 3-wire was the sending unit.

sorry I misspelled you name

No problemo See you at G110 in Carlisle with the rest of the VH :beer

DonO
 
R

Rollin's65

Guest
Gentlemen: I thank you one and all. I just got back from a long week out of town and couldn't get back to anyone. But I was thinking on everyone.
The fine job of black electric tape for wiring bundling got me. It came down one the driver side rear bumper strut. Frame to bumper and a small copper shine was there. Re-taped and wire loomed the whole bundle left to right. Not going to happen again.
I'm glad to admit that the three wires from the fuel sending unit in the tank was the problem. You guys were right on it!!!
I did replace the fuel tank and now I'm not sure where the 2 of the 3 wire re-connect.
I slid under the rear end and looking up at the sending unit I see the discharge tube facing toward the front of the car and a connecting pin to the left and right of the discharge tube.
Which is it? The tan to the left or the right??? Naturally, the black/pink on the other. The service mannual says not to get it wrong or major damage. Of course it doesn't tell us which is the S and I pins and which wire goes to each.

I thought I was just about ready until I looked at Magicv8's web site. I've got a few more things to do.

Thanks -- Everyone Rollin's65
 

Marlar

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magicV8

If you mean what you say(on your web site) about the 427 getting close to being furniture, I suspect there are a few folks who might just accomodate prying it loose from you. Yes?

:beer
 
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63 Resto Coupe-Red 65 Roadster
Which is it? The tan to the left or the right??? Naturally, the black/pink on the other. The service manual says not to get it wrong or major damage. Of course it doesn't tell us which is the S and I pins and which wire goes to each.

I thought I was just about ready until I looked at Magicv8's web site. I've got a few more things to do.

Thanks -- Everyone Rollin's65

If I understand this correctly, the two wires you are trying to connect are specific to both prongs, and with the physical size being different, you will have a problem in connecting them in any way other then in their proper place. Look inside the two rubber angled connectors, and you will see the size is different, so you probably couldn't get them wrong if you tried.

Stepinwolf
 

magicv8

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Going too fast over the hill.
magicV8

If you mean what you say(on your web site) about the 427 getting close to being furniture, I suspect there are a few folks who might just accomodate prying it loose from you. Yes?
:beer
Yeah - I've had offers, but when I want to sell my car, it's the big ugly thing in the corner of my garage that makes my roadster a candidate for Top Flight. Without it, the new buyer will have to find another 942 block, and that gets harder by the year. The effect on the value of the car would be a lot more than I'd get for the BB.

On the other hand, if you have 2 sb cars that you want to trade for my 66 and parts collection.............:L
 
R

Rollin's65

Guest
If I understand this correctly, the two wires you are trying to connect are specific to both prongs, and with the physical size being different, you will have a problem in connecting them in any way other then in their proper place. Look inside the two rubber angled connectors, and you will see the size is different, so you probably couldn't get them wrong if you tried.

Stepinwolf

Stepinwolf: After I got down there and looked at each pin and the female ends it sure was a no brainer. I sure feel stupid. Maybe I should have had a couple of cold ones before I looked at it.

Thanks for the pointer. I think I'll go hide in the corner

Rollin's 65
 
Joined
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Stepinwolf: After I got down there and looked at each pin and the female ends it sure was a no brainer. I sure feel stupid. Maybe I should have had a couple of cold ones before I looked at it.

Thanks for the pointer. I think I'll go hide in the corner

Rollin's 65

Don't feel bad, we all tend to think it is more difficult then it really is, until we get down and dirty. Then things seem so much clearer.

As for having a few cold ones before undertaking a task, I would not recommend it. Normally having a few before, is the reason we tend to think the job is harder then it actually is in the first place. :D

Good luck
Stepinwolf
 

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