P0123 fault code: what it means

P0123: Throttle position sensor A signal is too high. Usually puts the car in reduced-power mode.

Engine and gearbox (powertrain) · Costly if missed

Usual causes, most likely first

1. faulty TPS or electronic throttle body
2. corroded or spread connector pins
3. signal wire shorted to 5 V
4. open sensor earth

What the repair usually costs

• Throttle body clean and idle relearnNZ$90–NZ$190 · A$100–A$200
• Electronic throttle body replaceNZ$470–NZ$1,290 · A$440–A$1,190

Not sure what P0123 means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.