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Discussion Starter · #1 ·
John,
That wire which is connected to the "S" terminal goes through the firewall behind the fuse block and seems to be all wrapped up with a bunch of other wires in electrical tape but it is very hard to tell for sure!

As you know the NSS was disconnected and the previous owner jumpered the two purple wires. Why would have anyone done this and then wired that "S" terminal wire to the transmission so that it only starts in reverse?
I did turn the key on so that the back up lights came on and then slowly pulled the gearshift back out of reverse until the back up lights went off and I was still able to start the car. Does that mean I can eliminate anything being wired to the back up lights switch?
What I mean is the car was still in reverse but the back up lights weren't activated and it still started. As soon as I get it all the way out of reverse it won't start. All this happening of course with the clutch pushed in.
Is there a way to definately get the right "S" terminal wire followed inside the firewall so I know where that thing is hooked up to?

Thanks,

Scott
 

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"That wire which is connected to the "S" terminal goes through the firewall behind the fuse block and seems to be all wrapped up with a bunch of other wires in electrical tape but it is very hard to tell for sure!"

Does it go through the bulkhead connector or does it go through the firewall by itself? If it goes into the bulkhead connector I think it's the top right pin of the inside connector that it normally goes to.

"As you know the NSS was disconnected and the previous owner jumpered the two purple wires. Why would have anyone done this and then wired that "S" terminal wire to the transmission so that it only starts in reverse?"

The guy was having some issues with the rod that ties the transmission to the column. He defected the column NSS by jumping the two purples. He's also done something else. Otherwise by jumping the two purples the car would start in any gear.

"I did turn the key on so that the back up lights came on and then slowly pulled the gearshift back out of reverse until the back up lights went off and I was still able to start the car. Does that mean I can eliminate anything being wired to the back up lights switch?"

I don't he used the original back-up light switch doing whatever he did. Still guessing but I think there is another switch somewhere. Perhaps tied to the shifter linkage.

"What I mean is the car was still in reverse but the back up lights weren't activated and it still started. As soon as I get it all the way out of reverse it won't start. All this happening of course with the clutch pushed in."

I understand. Never suspected he used the reverse light switch for both the start and light function. Guessing some rewiring took place when you said a cloth wire was tied to the starter instead of a purple one.

"Is there a way to definately get the right "S" terminal wire followed inside the firewall so I know where that thing is hooked up to?"

Not real easily. I was hoping that it would have easier to chase under the dash.
 

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Discussion Starter · #3 ·
John,
The wire that comes from the S terminal on the solenoid is indeed purple(cloth must be some kind of heat shield as I pulled it back)and this wire connects to the bulkhead connector on the firewall. Standing at the front of the car looking at the firewall it is connected to the bottom right pin of the outside connector. What can I check next?
 

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Confusion on my part. Don't have a 70 schematic handy. Wouldn't expect it to go to the outside connector. That's the connector for all the forward lamps and other things in the front of the car. Maybe a difference used in a for speed car that I don't know about. The wire runs from the solenoid to that connector without going anyplace else that you can see?
 

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Discussion Starter · #5 ·
That's correct. It doesn't go anywhere else nor does it T-off and go elsewhere.

I swear that it used to start in any gear before I got under the dash and fixed that gauge cluster grounding problem you helped me with a few months ago. I wonder if i didn't mess something up while under there unhooking and rehooking wires? Any help you can offer would be appreciated.
 

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Trying to come up with an idea without having you rip into everything. Something doesn't quite make sense but see if it becomes clearer.
A, The two purples, under the dash are tied together.
B, The wire under the hood is one continuous piece.

We can see if there is continuity between the jumpered purples and the wire that attaches to the "S" terminal. We know that there is but we should have continuity no matter what gear the trans is in. This may tell us if the purple wire has been disturbed between the jumpered purple connection and the firewall without ripping up the harness under the dash. At least we can prove this out.

Disconnect the battery.
Disconnect the "S" wire.
Attach a jumper lead (clip lead with a piece of wire) to the "S" wire.
With an ohmmeter measure for continuity between the "S" lead and the jumpered purples with an ohmmeter. You should have continuity in all the trans positions.
If you do there is nothing else between the jumpered purples and the bulkhead connector. Have try something else.
If you don't have continuity in all trans positions, there's something else wired between the jumpered purples and the bulkhead connector.
 

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Discussion Starter · #7 ·
Did as you instructed and I've got continuity in all gears and neutral as well.
What's next?
 

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That's some good news. That says that there is no switch or anything between the jumpered purples and the solenoid. The wiring between the two items will allow the car to start in any gear. No problem with that wiring.

Take a look at the wiring going the other way from the jumpered purples. This is the wiring from the ignition switch to the jumpered purples.

Disconnect the battery.
Measure for continuity between the purple wire on the ignition switch connector and the jumpered purples. You should have continuity is all gears.

I still can't see how this could be a problem with the ignition switch itself. That doesn't really make much sense.
 

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Discussion Starter · #9 ·
Dumb question #1: Where's the ignition switch?

I'm assuming this is mounted on top of the steering column under the dash but not sure. Lead me by the hand! (what color wires go to this switch)

The jumpered purple wires go with a big bunch of wires wrapped in electrical tape behind the fuse panel.
 

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The ignition switch is on the top of the steering column. It's maybe 4 inches long and about an inch and a half wide. Colors to it are pink, brown, red, purple green, and orange (Think I got that right). One of the jumpered purples you already found out goes to the bulkhead connector and out to the "S" terminal. The other is supposed to go to the ignition switch without any stops along the way. I understand it's hard to see how the wires run. That's why I'm suggesting taking some measurements instead of tearing into the harness.
 

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Discussion Starter · #11 ·
Thanks,
I'll check it out tonight and let you know tomorrow.
 

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Discussion Starter · #12 ·
I've got continuity from the jumpered purple wires to the ignition switch above the column in any gear.

Another dumb question: Would I have continuity from the jumpered purple wires to all the female connections(purple, pink, orange, green, red and brown) on that switch because I did?

Any suggestions?
 

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Strange. You basically have continuity from the ignition switch all the way out to the solenoid. Not seeing why it won't start in any gear.
Maybe try measuring 12 volts, on the jumpered purples as you start the car in any gear. Be careful with the clutch/brake so you doen't run the car into a wall.
All those wires can look shorted together with the key on. They all get tied to 12 volts.
 
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