Speedo Help
Thread Starter
Staging Lane
Joined: Dec 2009
Posts: 78
Likes: 0
Speedo Help 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?
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?
On The Tree
Joined: Aug 2012
Posts: 190
Likes: 0
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.
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.
