Question about Wiring Diagrams
Thread Starter
Intermediate
Joined: Jan 2010
Posts: 37
Likes: 0
From: Houston TX
Question about Wiring Diagrams
WARNING! Electrical troubleshooting is not my strong point! 
Unfortunately, I don't know how to use a Digital Volt Meter properly.
The wiring diagrams I am finding in my shop manual and online show numbers in the various harness connections. I am assuming these are circuit numbers. I cannot seem to find any reference to these numbers in my shop or assembly manuals. I have determined that circuit 150 is a ground circuit. Does anyone know where to find the info that can tell me what these numbers mean? Is it a benefit?
I have a '76 vette that the previous owner swapped bodies with a '80 body. Needless to say, there are wiring issues. One of my favorite examples is the hole he drilled into the dash to install a toggle switch to operate the wipers and having the wrong wire hooked up to the sending unit for the fuel gage.
I am currently trying to find out why my right front clear marker light has no power. The left side works fine. I've traced a black wire with a white stripe back to a harness connection on the steering column. I'd like to find out what this wire is for and how it connects. I am wondering if connections are not right in the steering column. I fixed the horns on the vette all the way up to the column but the horn button does not work. So that has me wondering if there's issues in the column.
Anyhow, sorry for the long post. Any help is appreciated.
Unfortunately, I don't know how to use a Digital Volt Meter properly.The wiring diagrams I am finding in my shop manual and online show numbers in the various harness connections. I am assuming these are circuit numbers. I cannot seem to find any reference to these numbers in my shop or assembly manuals. I have determined that circuit 150 is a ground circuit. Does anyone know where to find the info that can tell me what these numbers mean? Is it a benefit?
I have a '76 vette that the previous owner swapped bodies with a '80 body. Needless to say, there are wiring issues. One of my favorite examples is the hole he drilled into the dash to install a toggle switch to operate the wipers and having the wrong wire hooked up to the sending unit for the fuel gage.
I am currently trying to find out why my right front clear marker light has no power. The left side works fine. I've traced a black wire with a white stripe back to a harness connection on the steering column. I'd like to find out what this wire is for and how it connects. I am wondering if connections are not right in the steering column. I fixed the horns on the vette all the way up to the column but the horn button does not work. So that has me wondering if there's issues in the column.
Anyhow, sorry for the long post. Any help is appreciated.
Thread Starter
Intermediate
Joined: Jan 2010
Posts: 37
Likes: 0
From: Houston TX
Ok. I found out that the black wire with the white stripe is for the right cornering light. It seems to go up into the steering column and connect somewhere (ignition switch?). For some reason there is no power to this wire. The orange wire next to it on the harness connection as power and goes to the left cornering light so it looks like I'm on the right track. I guess the next step is to tear apart the steering column.
Burning Brakes
Joined: Apr 2009
Posts: 807
Likes: 2
From: VIRGINIA BEACH VIRGINIA
Send me your e-mail address and I can send you some wiring diagrams that might help.
dangoodva@yahoo.com
dangoodva@yahoo.com
Intermediate
Joined: Jan 2010
Posts: 49
Likes: 0
From: Phoenix AZ
I had the same issue with my car and found a bad relay.(along with all my wires melted together) I have two of them one on the fuse block(blinker) and one clamped above the steering shaft under the dash( Flasher). This is on my chevelle SO take it for what it is. If you have any luck like me it will be the dumbest thing I'm sure. Good luck
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
WARNING! Electrical troubleshooting is not my strong point! Unfortunately, I don't know how to use a Digital Volt Meter properly.
The wiring diagrams I am finding in my shop manual and online show numbers in the various harness connections. I am assuming these are circuit numbers. I cannot seem to find any reference to these numbers in my shop or assembly manuals. I have determined that circuit 150 is a ground circuit. Does anyone know where to find the info that can tell me what these numbers mean? Is it a benefit?
I have a '76 vette that the previous owner swapped bodies with a '80 body. Needless to say, there are wiring issues. One of my favorite examples is the hole he drilled into the dash to install a toggle switch to operate the wipers and having the wrong wire hooked up to the sending unit for the fuel gage.
I am currently trying to find out why my right front clear marker light has no power. The left side works fine. I've traced a black wire with a white stripe back to a harness connection on the steering column. I'd like to find out what this wire is for and how it connects. I am wondering if connections are not right in the steering column. I fixed the horns on the vette all the way up to the column but the horn button does not work. So that has me wondering if there's issues in the column.
Anyhow, sorry for the long post. Any help is appreciated.
Unfortunately, I don't know how to use a Digital Volt Meter properly.The wiring diagrams I am finding in my shop manual and online show numbers in the various harness connections. I am assuming these are circuit numbers. I cannot seem to find any reference to these numbers in my shop or assembly manuals. I have determined that circuit 150 is a ground circuit. Does anyone know where to find the info that can tell me what these numbers mean? Is it a benefit?
I have a '76 vette that the previous owner swapped bodies with a '80 body. Needless to say, there are wiring issues. One of my favorite examples is the hole he drilled into the dash to install a toggle switch to operate the wipers and having the wrong wire hooked up to the sending unit for the fuel gage.
I am currently trying to find out why my right front clear marker light has no power. The left side works fine. I've traced a black wire with a white stripe back to a harness connection on the steering column. I'd like to find out what this wire is for and how it connects. I am wondering if connections are not right in the steering column. I fixed the horns on the vette all the way up to the column but the horn button does not work. So that has me wondering if there's issues in the column.
Anyhow, sorry for the long post. Any help is appreciated.
Try this for the column
1969-82 C3 Corvette Turn Signal Switch Wires
Colors, Order, & Functions
1969-1982 C3 Corvette wiring for the turn signals, hazard warning, brake lights, and horn followed the color coding that is charted below. Cornering lights were also included on 1980, 81, & 82 models. All wiring is routed up into the steering column and functions are actuated through the turn signal switch. The steering column wiring and the vehicle body harness wiring come together in a narrow long connector called the “harmonica connector”.
C3 CORVETTE TURN SIGNAL SWITCH WIRING
YEARS CONNECTOR COLOR WIRE COLUMN COLOR BODY FUNCTION
69-82 P White White 12v when brake pedal is pushed
69-82 N Dk Green Dk Green Right Rear Brake Light
69-82 M Yellow Yellow Left Rear Brake Light
69-82 L Purple Purple +12v source for turn signal power
1969 - 1982 K Brown 18 gage Brown 14 gage This provides the +12v for hazard flasher operation.
1969 - 1982 J Dark Blue 18 gage Dark Blue 20 gage - 2 wires Right Front Turn Signal Light
1969 - 1982 H Light Blue 18 gage Light Blue 20 gage - 2 wires Left Front Turn Signal Light
1969 - 1982 G Black 18 gage Black 20 gage Horn ground when horn button is pressed.
1969 - 1982 F Light Green 20 gage Pink/Black 20 gage These are the key buzzer warning circuit wires. Open with key removed. Shorted together with key in lock cylinder. Also open when key is turned in lock cylinder to Run position.
1969 – 1982 E Tan 20 gage Black 20 gage Same as F
1980, 81, & 82 C Black 18 gage Blk/Wht 18 gage Right Cornering Lamp
1980, 81, & 82 B Orange 18 gage Orange 18 gage Left Cornering Lamp
1980, 81, & 82 A Brown 18 gage Brown 18 gage Feed from headlight switch. This is the +12v source to power the cornering lamps when the headlights are ON.
With the connector disconnected none of these wires should be grounded (tied to chassis). In fact I don't think that they should tie to ground regardless of turn signal position, or activation of the hazard switch.
TurnSignalSwitchWires.doc
Colors, Order, & Functions
1969-1982 C3 Corvette wiring for the turn signals, hazard warning, brake lights, and horn followed the color coding that is charted below. Cornering lights were also included on 1980, 81, & 82 models. All wiring is routed up into the steering column and functions are actuated through the turn signal switch. The steering column wiring and the vehicle body harness wiring come together in a narrow long connector called the “harmonica connector”.
C3 CORVETTE TURN SIGNAL SWITCH WIRING
YEARS CONNECTOR COLOR WIRE COLUMN COLOR BODY FUNCTION
69-82 P White White 12v when brake pedal is pushed
69-82 N Dk Green Dk Green Right Rear Brake Light
69-82 M Yellow Yellow Left Rear Brake Light
69-82 L Purple Purple +12v source for turn signal power
1969 - 1982 K Brown 18 gage Brown 14 gage This provides the +12v for hazard flasher operation.
1969 - 1982 J Dark Blue 18 gage Dark Blue 20 gage - 2 wires Right Front Turn Signal Light
1969 - 1982 H Light Blue 18 gage Light Blue 20 gage - 2 wires Left Front Turn Signal Light
1969 - 1982 G Black 18 gage Black 20 gage Horn ground when horn button is pressed.
1969 - 1982 F Light Green 20 gage Pink/Black 20 gage These are the key buzzer warning circuit wires. Open with key removed. Shorted together with key in lock cylinder. Also open when key is turned in lock cylinder to Run position.
1969 – 1982 E Tan 20 gage Black 20 gage Same as F
1980, 81, & 82 C Black 18 gage Blk/Wht 18 gage Right Cornering Lamp
1980, 81, & 82 B Orange 18 gage Orange 18 gage Left Cornering Lamp
1980, 81, & 82 A Brown 18 gage Brown 18 gage Feed from headlight switch. This is the +12v source to power the cornering lamps when the headlights are ON.
With the connector disconnected none of these wires should be grounded (tied to chassis). In fact I don't think that they should tie to ground regardless of turn signal position, or activation of the hazard switch.
TurnSignalSwitchWires.doc
Melting Slicks
Joined: Dec 2006
Posts: 2,669
Likes: 3
From: Kingston Ontario
Haynes 68-82 corvette repair manual (ISBN 1 85010 723 8) is not the best source for specific year wiring; however it does list all the circuits in a two page listing! There is some value in these manuals.
Prior to tearing into the column you should be able to check individual components to troubleshoot.
Google "digital voltmeter/multimeter 101" for basic info on multimeter usage and instruction.
Your turn signals all working; except for the right front, would lead me to focus on that spot as opposed to the complete signal system. By that I mean, if your rear right signal is working when the signal was actuated from the turn signal lever,then the switch and associated steering column wiring is correct. In all likelihood the problem is localized at the front right light itself. ie: defective bulb, defective bulb socket or wiring to only that light. Most probable is a failed contact at the socket due to corrosion or a bad ground. Simple test for this is to use the power wire from that signal light position and while ensuring a good ground to the outside of a spare light apply the power lead to the centre contact. Your light should now work. You should have 12 v power and a good ground. If the test light works; then you need to determine whether the socket is faulty or the ground wiring to it. If the light doesn't work; then you have a power or ground problem. The use of the multimeter set for continuity will show a reading if the ground circuit is OK. The use of the voltmeter will determine if the power wire is OK.
Use a known working circuit to determine required results from the multimeter/voltmeter functions. Electrical is not that difficult to troubleshoot and if you plan to own your car for any period of time, this will not be the last time for electrical issues.
PS. welcome aboard!
Dan
Prior to tearing into the column you should be able to check individual components to troubleshoot.
Google "digital voltmeter/multimeter 101" for basic info on multimeter usage and instruction.
Your turn signals all working; except for the right front, would lead me to focus on that spot as opposed to the complete signal system. By that I mean, if your rear right signal is working when the signal was actuated from the turn signal lever,then the switch and associated steering column wiring is correct. In all likelihood the problem is localized at the front right light itself. ie: defective bulb, defective bulb socket or wiring to only that light. Most probable is a failed contact at the socket due to corrosion or a bad ground. Simple test for this is to use the power wire from that signal light position and while ensuring a good ground to the outside of a spare light apply the power lead to the centre contact. Your light should now work. You should have 12 v power and a good ground. If the test light works; then you need to determine whether the socket is faulty or the ground wiring to it. If the light doesn't work; then you have a power or ground problem. The use of the multimeter set for continuity will show a reading if the ground circuit is OK. The use of the voltmeter will determine if the power wire is OK.
Use a known working circuit to determine required results from the multimeter/voltmeter functions. Electrical is not that difficult to troubleshoot and if you plan to own your car for any period of time, this will not be the last time for electrical issues.
PS. welcome aboard!
Dan
Last edited by dannyman; Jan 9, 2010 at 12:15 PM.
Thread Starter
Intermediate
Joined: Jan 2010
Posts: 37
Likes: 0
From: Houston TX
Thanks for the input everyone.
Dannyman, I wanted to check the directional switch in the steering column because both power wires originate from the directional switch according to the wire diagram listed below and I wanted to make sure nothing was disconnected or fried.
http://www.nrjvette.com/johdotukset/...tte%201980.pdf
I located both the left and front cornering light wires on the steering column harness. Yesterday, I had power to the left side but not the right when I checked the wires entering the bulb sockets. For some reason today I have no power on the left side either. (shrug)
By the way, does it look like there is a fuse somewhere on the turn signal switch according to that wiring diagram???
In the process of putting the steering column back together. Which leads me to another question, when installing the HUB assembly back onto the spline, do you just use the large nut to work it back down the spline?
Dannyman, I wanted to check the directional switch in the steering column because both power wires originate from the directional switch according to the wire diagram listed below and I wanted to make sure nothing was disconnected or fried.
http://www.nrjvette.com/johdotukset/...tte%201980.pdf
I located both the left and front cornering light wires on the steering column harness. Yesterday, I had power to the left side but not the right when I checked the wires entering the bulb sockets. For some reason today I have no power on the left side either. (shrug)
By the way, does it look like there is a fuse somewhere on the turn signal switch according to that wiring diagram???
In the process of putting the steering column back together. Which leads me to another question, when installing the HUB assembly back onto the spline, do you just use the large nut to work it back down the spline?
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Use a test lite to test the black/white, orange and brown wires at the harmonica connector with the turn signal in the right positions.
Remember that the headlites must be on for the cornering lites to work.
The turn signal switch is a multi contact switch.
Other than the lever position, the front signals have nothing to do with the cornering lites.
Front signals, back signals and cornering lites, each side, each have separate outputs from the switch.
Yes you can put the hub further on with the nut if the splines are engaged properly.
Remember that the headlites must be on for the cornering lites to work.
The turn signal switch is a multi contact switch.
Other than the lever position, the front signals have nothing to do with the cornering lites.
Front signals, back signals and cornering lites, each side, each have separate outputs from the switch.
Yes you can put the hub further on with the nut if the splines are engaged properly.
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Thread Starter
Intermediate
Joined: Jan 2010
Posts: 37
Likes: 0
From: Houston TX
Wow! What a trip this has been so far. I am happy to report I have gotten all of my front marker, cornering, and turn signal lights working. After hours of troubleshooting, my biggest issue was using a 1156 bulb where I should have used an 1157! (yes, I can hear the laughter and the heads shaking!) 
I still cannot believe I did that let alone catch it right away 
Now I just have to get the rear drivers side and backup lights working and I can move on to the next issue.
Thanks for everyone's help!
I still cannot believe I did that let alone catch it right away Now I just have to get the rear drivers side and backup lights working and I can move on to the next issue.
Thanks for everyone's help!
