86 TPI diagnostic port under steering wheel
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From: Augusta, GA
Car: 1986 Iroc-Z
Engine: 305 bored .30 over
Transmission: Auto
86 TPI diagnostic port under steering wheel
Does anyone have a schematic for where the wires run to from the diagnostic port? I have a yellow organish color wire that is cut, it is coming from position E. I cannot find the schematic for this diagnostic connector at all, not even in the shop manual. I think it is the ALDL port? thanks
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From: MA
Car: '87 IROC/'68 SS
Engine: 5.7L/350
Transmission: 700R4/Muncie 4-spd
Axle/Gears: 3.27 9 bolt / 3.31 12 bolt
Re: 86 TPI diagnostic port under steering wheel
That's the serial data line. It also goes to M and connects to pin A8 of the ECM.
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Junior Member
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From: Augusta, GA
Car: 1986 Iroc-Z
Engine: 305 bored .30 over
Transmission: Auto
Re: 86 TPI diagnostic port under steering wheel
Got it on A8 to ECM. You say to M, I have many connections labeld M so please enlighten me a bit more please. I have made the connection over to A8 and waiting for more of your knowledge. Thanks for the help. Tony
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iTrader: (1)
Joined: Jul 2007
Posts: 1,141
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From: MA
Car: '87 IROC/'68 SS
Engine: 5.7L/350
Transmission: 700R4/Muncie 4-spd
Axle/Gears: 3.27 9 bolt / 3.31 12 bolt
Re: 86 TPI diagnostic port under steering wheel
The M port on the ALDL connector (lower right I think). So A8 on the ECM connects to both the E and the M contacts on the ALDL connector.
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