Trying to figure out what is going on with my VSS signal. My speedometer and tachometer work but I don't seem to be getting any signal to my ECU. Is that even possible? Does the signal go to the dash and then the ECU, or the other way around? I have an Adaptronic ECU and can look at the inputs to the ECU, but it shows steady state on the VSS sensor.

Thanks.

 

I think it may go to the cluster then the ECU, not sure. Take a look at the wiring diagrams to double-check.

Dale

 

VSS -> Speedometer -> Cruise Control and ECU

 

OP - Is your Adaptronic ECU a plug & play (uses stock harness), or was it wired in? If it was the latter, whoever wired it may have reversed the speedo sensor polarity for the input to the Adaptronic. Here's an excerpt from the FSM wiring diagram showing how the VSS is wired; note that the 2 wires ride thru the EM (emissions ECU harness) and the X-14 & X-15 connectors before getting to the dash speedo.

Went thru this drill when I rebuilt the wiring harness for my Link G4+ ECU. You basically need to tap the G/B wire from the speedo to the speedo input of your ECU, and the L wire on the speedo to your ECU's sensor ground.

 

It is a plug and play model. I will try to check the wiring leaving the cluster and see if I can trace the wire from the cluster to the ECU. I won't have a chance for a few days to try that, but if anyone has other ideas, all are greatly appreciated.

 

The speed sensor in the transmission is a 2-wire variable reluctance sensor, but the factory cluster converts that to a digital signal for the factory ECU. You shouldn't need to tap any wires, there's a wire at the factory ECU connector and it's described pretty clearly in the Powertrain Control Module (PCME) section of the factory service manual.