PeteB
GT40s Supporter
Got my Dakota Digital GPS unit. They've changed the design a bit, part number is now GPS-5-2.
With the GPS unit in the setting mode it outputs a 60mph signal. To test, I hooked up my android tablet to the OBD port via a PLX Devices Bluetooth dongle and used Dash Command to display the info from the ECU.
From the VSS plug on the GM wiring harness, I connected the purple/white wire to the GPS unit and the other wire to ground.
I first tried Speed output #1 which is the "standard speedometer" output. VSS speed read zero. So, I tried Speed output #2, "AC speedometer". Now I got a reading on the VSS speed. With the GPS unit set to 54000 pulses, the VSS reading from the ECU was 32mph, and with the pulses set to 128000, the VSS read 75mph. I think that's probably close enough for the ECU to be happy, so I'll leave it at 128000 and see how it works.
With the GPS unit in the setting mode it outputs a 60mph signal. To test, I hooked up my android tablet to the OBD port via a PLX Devices Bluetooth dongle and used Dash Command to display the info from the ECU.
From the VSS plug on the GM wiring harness, I connected the purple/white wire to the GPS unit and the other wire to ground.
I first tried Speed output #1 which is the "standard speedometer" output. VSS speed read zero. So, I tried Speed output #2, "AC speedometer". Now I got a reading on the VSS speed. With the GPS unit set to 54000 pulses, the VSS reading from the ECU was 32mph, and with the pulses set to 128000, the VSS read 75mph. I think that's probably close enough for the ECU to be happy, so I'll leave it at 128000 and see how it works.