Okay, just wanted to make sure as you stated you only turned the key to ON...
Burnt Wire
- Thread starter shittyslant6
- Start date
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shittyslant6
Well-Known Member
yes.
Sorry, just read again, the wire fried when the key was switched to the start position. attempted to crank, wire fried.
In which case, begin the investigation with the Starter relay (s1) and Ign 2 circuits.
Ign 1 and keyed Accessory should not be connected to power when the key is in Start, only the two circuits needed for starting.
shittyslant6
Well-Known Member
Cuda Al
Well-Known Member
Does your negative battery cable have a ground lead to the body? and or a wire from the engine to the body?
Alan
Alan
shittyslant6
Well-Known Member
I will look again,but I believe there is a ground wire going to the core support and from what I can remember, there is a wire that s disconnected with a cap on it but I will look again
67Dart273
Well-Known Member
OP I'd like you to go through a simple 1 2 3 list of what you did in order
For example
1....Because I had trouble with xxxxx I started to make a new *** cable
2....Then I.....yyyyy etc
Why did you drop the column? Was this before or after you burned something?
We need to isolate the short. One way you can do this is disconnect the batter NEG battery clamp and insert a big lamp in series, like an old headlamp or turn lamp. This will light the lamp when there is a load on the battery but it will limit current
Then start wiggling and removiing stuff, like fuses, to try and find the short.
Also if you wiggled or moved or removed anything (like the column) that is a sure indication that may be the "cause" of the short so to say
The major power distribution in the car that is NOT fused is actually pretty limited. One thing I'd do is inspect the dark blue "ignition run" connections out in the engine bay. This includes everything powered by the key in "run." Inspect the VR, the ballast, whatever ignition system you have, etc for shorts, frayed connections, bare wire, etc
For example
1....Because I had trouble with xxxxx I started to make a new *** cable
2....Then I.....yyyyy etc
Why did you drop the column? Was this before or after you burned something?
We need to isolate the short. One way you can do this is disconnect the batter NEG battery clamp and insert a big lamp in series, like an old headlamp or turn lamp. This will light the lamp when there is a load on the battery but it will limit current
Then start wiggling and removiing stuff, like fuses, to try and find the short.
Also if you wiggled or moved or removed anything (like the column) that is a sure indication that may be the "cause" of the short so to say
The major power distribution in the car that is NOT fused is actually pretty limited. One thing I'd do is inspect the dark blue "ignition run" connections out in the engine bay. This includes everything powered by the key in "run." Inspect the VR, the ballast, whatever ignition system you have, etc for shorts, frayed connections, bare wire, etc
shittyslant6
Well-Known Member
Ok, so.
1. I was trying to get the starter new starter to work as it did not spin over. I suspected a bad positive battery cable going to the starter as it was old and cracked.
2. A friend gave me a new positive battery cable that was bigger than the old one.
3. I connected the new cable and all of the wires back up to the car.
4. I went to try and start the car and nothing happened. looked at the ammeter and it was pegged at discharge.
5. With the key still in the start position, I heard a small sizzling noise and saw smoke coming from under dash. then I turned the key off.
6. When I looked under the dash a wire that went to nothing, (just ground at both ends to the column bracket) was burned through.
7. Curious if the wire was connected to another wire going to the start switch on the other side of the bracket, I dropped the column to get a better look at the wires.
8. I didn't see any wires going to the burnt ground and no other wire was burnt.
9. put the column back and checked all the fuses, grounds, continuity, etc. everything seems fine but starter will not kick over still.
hope that clears everything up.
1. I was trying to get the starter new starter to work as it did not spin over. I suspected a bad positive battery cable going to the starter as it was old and cracked.
2. A friend gave me a new positive battery cable that was bigger than the old one.
3. I connected the new cable and all of the wires back up to the car.
4. I went to try and start the car and nothing happened. looked at the ammeter and it was pegged at discharge.
5. With the key still in the start position, I heard a small sizzling noise and saw smoke coming from under dash. then I turned the key off.
6. When I looked under the dash a wire that went to nothing, (just ground at both ends to the column bracket) was burned through.
7. Curious if the wire was connected to another wire going to the start switch on the other side of the bracket, I dropped the column to get a better look at the wires.
8. I didn't see any wires going to the burnt ground and no other wire was burnt.
9. put the column back and checked all the fuses, grounds, continuity, etc. everything seems fine but starter will not kick over still.
hope that clears everything up.
No. Then there would be no power to the key switch.
Lets step back for moment.
Voltage describes the energy level. It's like pressure in a pipe. In your house there's 60 psi in the house water lines. Maybe more in certain places, less in others. That 60 psi is there when all the valves are shut. No water flowing. When a sink faucet is opened, the water flows from high pressure to low pressure. There's still close 60 psi in the lines.
Amperage describes the electrons flowing. That's like the water flowing - gallons per minute. With the sink faucet open, its very little flow. If the entrance pipe was broken, that would be huge flow.
The column connector in your '70 looks something like this. (this is a '74, things like colors may be a little different)
The wire that connected the column to the dash is a grounding wire. Someone above explained one thing it does is ensure a good connection for the horn relay. On cars with column selectors, it also serves to insure good grounding for the gear position lamp.
Here's a '70 Duster - also hacked but the remaining the colors are probably the same as yours.
shittyslant6
Well-Known Member
So,
1. put a big lamp in the circuit to limit current so I don't fry anything else.
2. then I put the key in Start position and start looking around for shorts. VR, ballast, etc.
3. If nothing turns up, inspect the start/ign. switch and check for shorts or bad ground.
correct?
1. put a big lamp in the circuit to limit current so I don't fry anything else.
2. then I put the key in Start position and start looking around for shorts. VR, ballast, etc.
3. If nothing turns up, inspect the start/ign. switch and check for shorts or bad ground.
correct?
MiradaMegaCab
Well-Known Member
Sounds like a bad negative battery cable.
67Dart273
Well-Known Member
^^Basically^^
You need to "shed the load" so you can isolate the problem. Since the problem (right) only shows in the "start" position, you will have to eliminate other loads so the lamp goes dim, and "is only lit" by the short
So disconnect the wire on the starter relay that connects to the "square" screw on the starter solenoid. This is the solenoid connection. It actually does NOT go through the ammeter but it will light your test lamp
Try again if the lamp is still bright
Disconnect either of the "push on" terminals on the starter relay
If the lamp is still bright
Disconnect the VR connector, it should not make much difference.
Next disconnect the ballast resistor
If none of these make much difference in the lamp brightness, start at the "dark blue" at the ballast resistor and chase it back to the bulkhead connector in the engine bay. Look for frayed/ broken insulation, burned areas, or something "non original" spliced into the blue wire
Examine the coil wire and look for damage/ short. Go back to the ballast and examine the remaining terminal should have a brown and another wire. Examing that for damage. Disconnect the coil+ wire. Try again twist the key look for any change in lamp brightness
Now go down to the alternator and examine the light blue wire, look for burned/ bad insulation, chase that wire back to the bulkhead, looking for damaged harness, etc.
If none of this gets you anywhere things are going to get complicated
You need to "shed the load" so you can isolate the problem. Since the problem (right) only shows in the "start" position, you will have to eliminate other loads so the lamp goes dim, and "is only lit" by the short
So disconnect the wire on the starter relay that connects to the "square" screw on the starter solenoid. This is the solenoid connection. It actually does NOT go through the ammeter but it will light your test lamp
Try again if the lamp is still bright
Disconnect either of the "push on" terminals on the starter relay
If the lamp is still bright
Disconnect the VR connector, it should not make much difference.
Next disconnect the ballast resistor
If none of these make much difference in the lamp brightness, start at the "dark blue" at the ballast resistor and chase it back to the bulkhead connector in the engine bay. Look for frayed/ broken insulation, burned areas, or something "non original" spliced into the blue wire
Examine the coil wire and look for damage/ short. Go back to the ballast and examine the remaining terminal should have a brown and another wire. Examing that for damage. Disconnect the coil+ wire. Try again twist the key look for any change in lamp brightness
Now go down to the alternator and examine the light blue wire, look for burned/ bad insulation, chase that wire back to the bulkhead, looking for damaged harness, etc.
If none of this gets you anywhere things are going to get complicated
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shittyslant6
Well-Known Member
even after I replaced it?
MiradaMegaCab
Well-Known Member
Temporarily hook up jumper cables from your engine to the chassis.
Temporarily hook up jumper cables from the negative battery post to the engine....
Temporarily hook up jumper cables from the negative battery post to the engine....
MiradaMegaCab
Well-Known Member
Apparently I missed the part of you replacing the Negative battery cable.
Did it attach to the engine and body?
67Dart273
Well-Known Member
Some of what you are doing:
Since the short seems to "happen" when you have the key in "start" than we need to determine "where all" power goes when in start
The key switch gets UNFUSED battery input form the ammeter circuit, live at all times
outputs from the key:
1...With the key in "run" the IGN1 "run" usually dark blue is live as well as the ACCESSORY buss below
2...With the key in ACCESSORY only the ACC buss is live. This feeds the buss in the fuse panel that fuses feed radio, heater, wipers, etc
With the key in "start" the IGN1 "run" circuit and the ACC buss ARE DEAD
ONLY the following 2 circuits are live:
A....The yellow "start" wire feeds out through the bukhead and goes to one "push on" starter relay coil terminal With the clutch depressed, or the trans in P or N the neutral switcn grounds the other relay coil terminal so the engine cranks
B..Since IGN1 "run" is now dead we need power to ignition. The IGN2 brown goes from the key through the bulkhead, to the coil+ side of the ballast resistor.
SO THERE IS NOT MUCH "stuff" powered in "start."
What else DOES have power is all the stuff in the car that is "hot" at all times, like dome lights, head lights/ tail lights etc etc anything wired to the "hot" buss in the fuse panel. BUT THESE COMPONENTS are not affected by the "start" position
Since the short seems to "happen" when you have the key in "start" than we need to determine "where all" power goes when in start
The key switch gets UNFUSED battery input form the ammeter circuit, live at all times
outputs from the key:
1...With the key in "run" the IGN1 "run" usually dark blue is live as well as the ACCESSORY buss below
2...With the key in ACCESSORY only the ACC buss is live. This feeds the buss in the fuse panel that fuses feed radio, heater, wipers, etc
With the key in "start" the IGN1 "run" circuit and the ACC buss ARE DEAD
ONLY the following 2 circuits are live:
A....The yellow "start" wire feeds out through the bukhead and goes to one "push on" starter relay coil terminal With the clutch depressed, or the trans in P or N the neutral switcn grounds the other relay coil terminal so the engine cranks
B..Since IGN1 "run" is now dead we need power to ignition. The IGN2 brown goes from the key through the bulkhead, to the coil+ side of the ballast resistor.
SO THERE IS NOT MUCH "stuff" powered in "start."
What else DOES have power is all the stuff in the car that is "hot" at all times, like dome lights, head lights/ tail lights etc etc anything wired to the "hot" buss in the fuse panel. BUT THESE COMPONENTS are not affected by the "start" position
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shittyslant6
Well-Known Member
****, sorry, no I did not replace the negative I replaced the positive. sorry.
shittyslant6
Well-Known Member
and yes, the old one is attached to both engine and body. I will try and get a new one to see if that is the problem.
Key OFF. Lights OFF, Dome light off, Foot Off the brake.
If there is 12.7 Volts between the battery positive and the ground, then there is 12.7 Volts in every line that is connected to the battery.
No current is flowing out of the battery.
When the key is turned to start, here what is supposed to happen.
Initially current flows through the key switch to the starter relay (S2 in the sketch below) and back to ground.
Whenever the distributor points are closed current flows through the coil and back to ground.
Next, if the relay had closed this would have let the power from the battery go to the starter's solenoid.
Then starter will connect and draw power.
Current returns through the grounds.
Based on the meter and the other evidence I suspect a short in the starter wire (yellow) or Ignition 2 (brown).
However there is a possiblity of a return wiring issue that others have brought up.
If there is 12.7 Volts between the battery positive and the ground, then there is 12.7 Volts in every line that is connected to the battery.
No current is flowing out of the battery.
When the key is turned to start, here what is supposed to happen.
Initially current flows through the key switch to the starter relay (S2 in the sketch below) and back to ground.
Whenever the distributor points are closed current flows through the coil and back to ground.
Next, if the relay had closed this would have let the power from the battery go to the starter's solenoid.
Then starter will connect and draw power.
Current returns through the grounds.
Based on the meter and the other evidence I suspect a short in the starter wire (yellow) or Ignition 2 (brown).
However there is a possiblity of a return wiring issue that others have brought up.
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What burned is a ground connecter.
As the column is bolted to the dash and firewall there still is probably a ground path, just not as good.
shittyslant6
Well-Known Member
Ok, thank you guys so much, I think I finally understand what happened and I will try the things you all suggested and pray that it is just a short in the system.
Bugman
Well-Known Member
Bugman
Well-Known Member
Here's a better diagram, look by the red lines
Bugman
Well-Known Member
Bugman
Well-Known Member
The column you're dealing with is and impact energy absorbing steering column, it is not rigidly mounted anywhere. There are plastic spacers designed to slide and or break away if need be in the event of an accident. I can see one in your pictures. At the bottom that column is surrounded by a rubber weather boot the boot is bolted to the firewall . The column has no mechanical connection to the fire wall. It supposed to be able to move in case of accident
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