P0641 fault code: what it means

P0641: Sensor reference voltage A circuit (5 V supply).

Engine and gearbox (powertrain) · Costly if missed

Usual causes, most likely first

shorted sensor on the shared 5 V supply (e.g. rail pressure, MAP)
wiring chafe
ECM

P0641 by make

Isuzu

Sensor reference voltage A circuit (5 V supply).

Usual causes: shorted sensor on the shared 5 V supply (e.g. rail pressure, MAP); wiring chafe; ECM

What the repair usually costs

High-pressure fuel pump (GDI petrol or common-rail diesel)NZ$1,140–NZ$4,280 · A$1,060–A$3,800

Not sure what P0641 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.