LonghornSS

Hey guys I just recently completed an LS2 swap and have been slowly picking away at some of the bugs in the car. so now I am at the Speedo, it is an Aftermarket Electronic unit.
I have tried the calibration procedure while connected to the Speed output on the ECM, (Street and Performance harness) and I get nothing.

I have tried using a dakota digital OBD II interface, It drives the Tack and the Engine light just fine but still no speedo.

I can use a scan tool and get the speed signal so I know the ECM is generating it.

Any help?

Is there a way to check the output on the wire from the ECM?

Hart_Rod

iTrader: (3)

Do you know what wire you are using to drive the speedo? Can you post the tune? If the signal is not set correctly in the tune, it won't work.

LonghornSS

I am using the wire that as provided in the harness for the speedo. I am not sure which pin it is in the ECM I could take a look but the car is not handy.

I could probably post an HP tuners file

Hart_Rod

iTrader: (3)

email me your tune, robhartley@aol.com

Mike_hawk

What speedometer are you using? My speedometer -summit 6 gauge digital- showed a speed before it was calibrated, it was just wrong(about half the actual speed). The PCM is looking for a certain number of pulses from the transmission per mile to get your speed and each gauge is set up for a certain number of pulses. I would check the wiring from the PCM to the gauge to make sure it's not broken. It sounds like it's an issue with wiring or programming; either the speed signal from the PCM, or the pulses that the gauge is getting from the PCM is outside of the limits for your gauge.

Hart_Rod

iTrader: (3)

Most speedos are programmable. I have the Dakota Digital VHX series and it is programmable from 2K PPM up to 256K PPM. I think the speed output is either turned off in his tune or his wiringis incorrect.