Autometer Speedo hook-up w/ LT1
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
Originally Posted by ninetyfivevette
The A4 trans speed sensor outputs a sine wave, the ZF6 outputs a square wave, just FYI. I should also mention I can only speak for the 4L60E, I don't know about the 700R4...
I assume they're talking about a ZF6 trans. "The Vehicle Speed Sensor (VSS), is a pulse counter type input that informs the ECM (ZR1 doesn't have a PCM) how fast the vehicle is being driven. The VSS system uses a Permanent Magnet mounted at the output shaft of the transmission, to produce AC (sine wave) voltage pulses that increase or decrease with the speed of the wheels."
Are you saying on a 95 LT1/ZF6 Corvette unlike the ZR1, the output signal from the transmission is a square wave and not a sine wave? If so, please post where you found this information. Thanks.
Thread Starter
Pro
Joined: Jun 2001
Posts: 708
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From: Florida
Originally Posted by jburnett
I just connected that to the "Sig" on the speedo and left the "out" unplugged...Works perfectly. I should mention this IS an aftermarket wiring harness, though.
-Jeb
-Jeb
)BTW: I'm also using an aftermarket harness (Painless Wiring), but it's using all the same wires as the stock F-body harness(GM color-coded as well)... maybe I should have mentioned that???
OK, I probably won't get to the dash removal for a day or two, then will have to wait again for Autometer's suggestion once they know the date of manufacturer...
To be continued....
Thanks again everyone!
Burning Brakes
Joined: Jan 2002
Posts: 1,228
Likes: 1
From: Dallas Texas
Originally Posted by Hooked on Vettes
Are you saying on a 95 LT1/ZF6 Corvette unlike the ZR1, the output signal from the transmission is a square wave and not a sine wave? If so, please post where you found this information. Thanks.
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
Originally Posted by ninetyfivevette
Sorry to bring this up from the dead, but that is correct. I am cannot remember where/who I got my information from since it was over a year ago, but the FSM clearly states the speed sensor outputs a sine wave and the PCM converts it to a square wave to feed to the CCM, etc. Again, sorry to put misinformation out there.
He still hasn't posted if he got it working.
Thread Starter
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Joined: Jun 2001
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From: Florida
OK...popped-out the dash cluster and noticed that the wire going into the "sig" terminal was hanging on by a thread. I put it back in securely (it fits tight, so I must have pulled on the wire accidentally during re-install or something???) and all is GOOD Calibrated it on the expressway (I sure hope those mile markers are accurate!) and everything seems fine (no tranny shifting problems, at least).
So the "T" method does work best in this situation (Nothing connected to the "OUT" terminal). Still not sure why the loose wire would have affected the shifting, but not going to worry about that now
)
Thanks again everyone
Calibrated it on the expressway (I sure hope those mile markers are accurate!) and everything seems fine (no tranny shifting problems, at least).So the "T" method does work best in this situation (Nothing connected to the "OUT" terminal). Still not sure why the loose wire would have affected the shifting, but not going to worry about that now
)Thanks again everyone
