99+ pcm swap tachometer issue
Thread Starter
Staging Lane
iTrader: (3)
Joined: Feb 2013
Posts: 62
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From: San Antonio, Texas
99+ pcm swap tachometer issue I hope this is the right place for this.
I have a 99+ LS1 PCM and engine harness in my 98 body with 98 body harness.
I have almost all of the guages working except the tachometer. I know the tach has a feed on #10 coming out of the PCM and on one of the shock tower plugs for the traction control. If I tap into either one of these wires and run a new wire to my dash harness will this give the appropriate signal to run the tachometer on a 98 dash? Ive read on here where people run their aftermarket tachs off of these wires but wanted some more information before I go splicing and running wires aimlessly.
THANKS
I have a 99+ LS1 PCM and engine harness in my 98 body with 98 body harness.
I have almost all of the guages working except the tachometer. I know the tach has a feed on #10 coming out of the PCM and on one of the shock tower plugs for the traction control. If I tap into either one of these wires and run a new wire to my dash harness will this give the appropriate signal to run the tachometer on a 98 dash? Ive read on here where people run their aftermarket tachs off of these wires but wanted some more information before I go splicing and running wires aimlessly.
THANKS
Thread Starter
Staging Lane
iTrader: (3)
Joined: Feb 2013
Posts: 62
Likes: 0
From: San Antonio, Texas
Well, after piecing together info from various off topic threads I figured it out and got my 98 dash tachometer working with my 99 pcm and engine harness. I added a wire into pin G on C105 (I wont have traction control) and ran that wire in through the firewall and plugged it into pin D C230 on the 98 Dash harness. And now the tachometer works!
The G C105 would be a great spot for those of you wanting to run aftermarket tachometers to tap into the harness especially if you dont have traction control or deleted it. it is much easier to access and wire tuck the new wire than the wire going into the PCM or other spots on the engine harness.
The G C105 would be a great spot for those of you wanting to run aftermarket tachometers to tap into the harness especially if you dont have traction control or deleted it. it is much easier to access and wire tuck the new wire than the wire going into the PCM or other spots on the engine harness.
Did you have traction control before? I ask because I don't have traction control and my tach doesn't work after the swap, nor my shift light since they are off of the same source I'm assuming. However, my rpm signal is able to be logged.
Also, I'm not sure which plug your speaking of when referring to C105.
Also, I'm not sure which plug your speaking of when referring to C105.
