Good morning

Today I present the following case solved in the Help Desk

Alfa Romeo Mito 1600mjet engine won't start

In the engine ecu diagnosis, error P0651 is present: reference voltage sensor B - circuit interrupted

In order to proceed with the solution, we have carried out a number of tests, which we indicate below:

we disconnected the connections of the following components one by one and then tried to clear error p0651.

1. Track 2 accelerator potentiometer
2. Rail pressure sensor
3. Supercharger pressure sensor
4. Turbo position sensor

After disconnecting each component, we arrived at test 4, i.e.

we disconnected the connector of the Turbo position sensor.

Error p0651 was deleted from memory .

We tried to start the engine and it started regularly.

Solution: Replace the component  Turbo position sensor mounted on the turbocharger

or overhaul the turbo compressor.

good reading

Best regards Antonio