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Old 09-08-2004, 11:16 AM   #1
TwinTurbo
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What's the light blue/ green wiring for??

What's this wiring for? The wiring comes through the firewall through a small hole just left from the fusebox. Is this from the cruis control system???


Marck
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Old 09-08-2004, 12:40 PM   #2
smokinn
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What year and motor size might help.
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Old 09-08-2004, 12:41 PM   #3
TwinTurbo
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83 used to be 305 / TH350
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Old 09-08-2004, 01:21 PM   #4
swervin ervin
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On my 85, there is a grommet beside the fuse box, engine side. It's not a flat grommet but bulges out. Anyway there is a light blue wire and a green wire coming out. The light blue wire goes to the low vac switch for tranny lockup. The green wire goes to the coolant temp sender. Is your TH350 a TH350C with lockup?

Hope this helps.
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Old 09-08-2004, 04:34 PM   #5
TwinTurbo
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Mine has a 400 now. The blue and green wire share a connector
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Old 09-08-2004, 07:41 PM   #6
swervin ervin
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I have changed so much wiring on mine, it may not be the same. I can't remember if I've changed any wiring coming out the grommet or not. It's very possible that both wires at one time went to the low vac switch. The stock wiring for the lockup was a total mess with wires going every which way. My wires may just be where I reran my lockup which consists of one wire now, and the other (green) wire may be where I ran a new temp sender wire. I'm just not sure.

Do you have a low vac switch still mounted on the firewall, or did you ever have one? If you do, see if the plug fits the switch. It's a tiny plug and will only fit it and nothing else.
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Old 09-08-2004, 07:51 PM   #7
MidnightBlues
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Hi Marc,

The green wire is a test wire for the (low vac switch) lockup system.
The blue wire is supposed to go to the brake cancel switch.
But you don't need all this with a 400 tranny.

greetz :p
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Old 09-08-2004, 08:04 PM   #8
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ahh.thanks, torque converter lockup control ... don't need that indeed
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