P0121 Toyota - probability of an easy fix for Toyota Yaris 2008

Question

The most obvious things to do are clearly:

1. Clean the throttle pedal, TPS and associated wiring.
2. Check TPS wiring for connection problems and damage.
3. If found necessary, change the TPS wiring and/or the TPS unit.
4. Check the voltages obtained at the engine end of the TPS wiring are in range and as expected, and do not seem subject to intermittent faults.

Question

If I have this done, what is the probability that this will solve the problem?
Is it worth paying to have these fairly simple things done, on the understanding that it might not solve the problem?

[My Toyota Main Dealer is currently quoting - worst case - for rewiring the whole car!]

Answer 1

P0121 Throttle / Pedal position sensor / Switch " A " circuit range / Performance problem

The TPS is built into the throttle body, When you get this code this is a difference in the throttle opening angle (VTA) , there is VAT 1 and VTA 2. if any of the VTA deviates from its normal signal the ECM codes it as a TPS malfunction. If this is not a harness fault the throtttle body needs to be replaced. The probabilty of having the simple things done is the best approach. and the usual fix is a new throttle body in order to replace the TPS.