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Old 09-23-2018, 05:31 PM   #1
rcazwillis
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Transmission Wiring Harness

Putting underhood wiring back in Zane's 71. Turbo 400 transmission. Two wires go to the kickdown on the transmission. In the same bundle, but branching out, is 3 wires going to a flat white two plug. Wire colors are blue, brown, brown white. The two browns go to the same terminal.
I cannot figure out where this plug is supposed to go. Any ideas?

2nd question, Starter has two wires, purple and yellow. Purple is start, yellow appears to go back to gauge cluster. Is the yellow just a power feed? Why does it go to the starter. My problem is the starter I have does not have the post for the yellow wire. Can the yellow wire just go to a power feed?
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Old 09-23-2018, 05:46 PM   #2
RustyPile
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Re: Transmission Wiring Harness

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Originally Posted by rcazwillis View Post
2nd question, Starter has two wires, purple and yellow. Purple is start, yellow appears to go back to gauge cluster. Is the yellow just a power feed? Why does it go to the starter. My problem is the starter I have does not have the post for the yellow wire. Can the yellow wire just go to a power feed?
If you have installed an HEI distributor, you don't need the yellow wire.. Normally, it's used on points type ignitions to bypass the resistor wire going to the (pos) terminal of the ignition coil.. The yellow wire connects to the starter solenoid on the Terminal opposite where the purple wire connects. If you don't have an HEI, AND your starter solenoid doesn't have that 4th terminal, you'll need to replace it with one that does.. No need to replace the complete starter, just the solenoid...
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Old 09-23-2018, 06:15 PM   #3
rcazwillis
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Re: Transmission Wiring Harness

I replaced the engine harness with one from Brothers for an HEI. There is no yellow for the coil in the wiring harness. I see now where the pink wire for the HEI goes to the terminal where the yellow wire connected in the factory harness. The yellow at the starter must branch off the pink at some point. Guess I will cap the yellow by the starter.
Thanks for the help.

Any one have an idea where the flat plug goes out of the trans?
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Old 09-23-2018, 06:52 PM   #4
aerotest
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Re: Transmission Wiring Harness

The trans kick down switch is a separate harness. Can be purchased or easily fabricated.
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Old 09-23-2018, 07:47 PM   #5
rcazwillis
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Re: Transmission Wiring Harness

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Originally Posted by aerotest View Post
The trans kick down switch is a separate harness. Can be purchased or easily fabricated.
With the exception of the one crumbling flat connector, all is good with the harness. However, I can't figure out where the one plug goes. One two wire plug goes to the driver side of the transmission. Where does the flat one go?
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Last edited by rcazwillis; 09-23-2018 at 07:53 PM.
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Old 09-23-2018, 07:55 PM   #6
chewychevy67
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Re: Transmission Wiring Harness

Pictures would probably help identify the wires.
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Old 09-23-2018, 07:55 PM   #7
rcazwillis
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Re: Transmission Wiring Harness

The wiring for the trans is all connected to the two relays (I think that is what they are) on the driver side firewall. The three wires from the flat plug all connect to one or the other relay.
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Old 09-23-2018, 08:06 PM   #8
rcazwillis
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Re: Transmission Wiring Harness

Pictures. One of the two relays on the firewall. One of the plug. One of the green wire with no end on it, which is another mystery. Green is in same wiring group going to "relays". I don't believe these are a relay. Two plugs on one, three on the other.
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Old 09-24-2018, 12:13 AM   #9
lil hoodlum
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Re: Transmission Wiring Harness

Those relays and associated wiring are apart of the TSC, Trans Spark Control.

Many people just delete them.
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