DIY - Bypassing Tire Pressure Warning System (TPWS / TPMS)

[CTScott]

Originally Posted by Tamago

ah cool so where they enter the ENGINE ecu they're pulse signals, then they go out to the cluster as pulses (correct me if i'm wrong, i recollect setting up a Defi VSD heads up display, and grabbed pulse signals for tach/speed) and the ECU also sends analog outputs to the TPMS?

do you have a wiring diagram of the ECU?

The ECU sends the same pulsed signal to the cluster and the TPWS. The Combo Meter has a microcontroller, which reads the tach and VSS inputs directly, as well as a CAN bus interface to get the odo data and MIL input from the ECU. All of the "data" signals are 12 V, so the microcontrollers have to level shift them to use them (via optoisolator, A-D, etc.).

The Defi's micro would have to do the same thing. By the way, was the Defi VSD worth the money?

For the wiring diagrams, I just have the 09 service manual.