LS1 tach signal pull up mod using stock LT1 tach guage cluster
#1
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Is the tach resistor signal pull up mod the same as aftermarket gauge if I'm using a stock LT1 tach gauge on a LS1 PCM conversion?
I've searched and read a bunch of folks using a 680 ohms resistor on pin#10 C2 Red and connecting other end of the resistor to a fuse protected 12v+ key source when using aftermarket tachs. Haven't seen anything for stock LT1 tach gauge though.
I have a 1996 LT1 to LS1 coil on plug 24x conversion from EFIconnection and using HP Tuners software without access to TunerCat, otherwise I'd just do it in the tune.
I've searched and read a bunch of folks using a 680 ohms resistor on pin#10 C2 Red and connecting other end of the resistor to a fuse protected 12v+ key source when using aftermarket tachs. Haven't seen anything for stock LT1 tach gauge though.
I have a 1996 LT1 to LS1 coil on plug 24x conversion from EFIconnection and using HP Tuners software without access to TunerCat, otherwise I'd just do it in the tune.
#4
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
gotcha. In the the [Engine] tab, off to the right-side is the Tach Output. I forgot about those.
Ok, setting both Hi and low to 3. Thanks. Was at 6/6. I'll give it a test drive at lunch.
Ok, setting both Hi and low to 3. Thanks. Was at 6/6. I'll give it a test drive at lunch.
#5
Launching!
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
You never said if that was enough to get your tach working.
My '96 Tahoe tach seems so sad sitting at 0...
My harness guy ran out of time working on my truck and didn't spend much time working with the info I supplied about the 1k pull-up resistor, so mine's still dead.
Got another session I'm going to get the truck to him for, but if this fixes it, that's even better...
Mine's an '01 ECM.
Thanks,
-Kyle