Fault Code P0642

[RichieC]

Good morning everyone,

I’m new to this forum but looking through the site there are so very knowledgeable members so I’m hoping you may be able to help.

I’m a mechanic and I’ve been looking into a fault on a transit this week.

2009 Mk7 2.4 140bhp

It came in with what sounds like diesel knock, we carried out a diagnostic check and the only fault code showing was P0642 Low Voltage Circuit A.

I have checked through live data and noticed that the rail pressure was showing 58000-61000 kph on idle but we had No Injector Correction Values Showing!

The work completed so far:

New PRV Valve
New Rail Sensor
New SCV Valve
Fuel learn procedure
New Batters X2
Check the loom for and charging or damage
Checked the fuse box in the engine bay for corrosion

The vehicle did run for 5-10 run up tests perfectly with all the live data showing and we thought the vehicle was complete and then came in yesterday to arrange collection with the customer and it was back to the original fault and diesel knock.

Any help would be appreciated as I feel it’s an electrical fault somewhere.

[knobby1]

P0642 it is my apologies.

Lord Knobrot

[bambi mk 1]

P0462 is a faulty fuel tank level sensor or possibly the wiring to/from it..

Lord Knobrot

Glasses Knobby P0642 the op posted

[knobby1]

Glasses Knobby P0642 the op posted

Oh dear...l'm bloody dyslexic now...

Lord Knobrot

[heinkok4]

Hi Guys

Yesterday my van died on me and according to Forscan it is the same code - P0642 Sensor A voltage circuit low

My van is an old 2008 85 Hp. Did anyone found a solution to the problem? I have checked fuses and connectors, but no luck so far.

Any help or guidance would be appreciated

Cheers