Hi everyone,

I need some of your valued advice if possible please

We own a 2020 Focus Vignale 1.0 petrol eco boost from new and have done 14000 miles

its been problem free until a couple of weeks ago, then on a journey back from Heathrow the orange engine light came on.

i took it to a local garage (not Ford main dealers) and the following codes came out on the print out

P2096-00 Post Catalyst Fuel Trim System too lean Bank 1

U2 100-00 Accessory Protocol Interface Module - Initial Configuration not complete

P2096 Post Catalyst Fuel Trim System Too Lean Bank 1

The garage advised they cleaned the fuel sensor and cleared the codes, all would be fine

Fast forward another 2 weeks the amber light comes back on, so back to the garage

Print out this time reads

P008B-00 Low Pressure Fuel System Pressure too high 

P2096-00 Post Catalyst Fuel Trim System too lean bank 1

U2100-00 Accessory Protocol Interface Module, initial configuration not complete 

Garage advised they cleaned the fuel sensor again said we need to drive it more, that was 1 week ago

Now the amber engine light is on again,

Car has been well looked after and main dealer serviced every year even though it says every 2 years,

If I take it to the main dealers I’m afraid they’ll want to take my arms and legs off,

Do try and find a local Ford Indie?

Could it be the battery is on it’s way out already but stop/start still works?

Are these fault codes common and what to do please?

I’m loosing the will now,

I would value your kind expertise please?

Thank you in advance,

Kind regards,

Steve

 

Update - okay so I figure the battery is 5 years old and may be causing the temporary fault codes so going to buy a new battery and delete the codes and see if they come back.

just hope I’m doing the right thing?

Any thoughts please?

I very much doubt if this problem is related to the battery.

Thank you for your response, why please?

Seems odd these fault codes all popped up at once and it’s only done 14k

On 8/30/2025 at 7:31 PM, FocusFan100 said:

P2096-00 Post Catalyst Fuel Trim System too lean Bank 1

U2 100-00 Accessory Protocol Interface Module - Initial Configuration not complete

P2096 Post Catalyst Fuel Trim System Too Lean Bank 1

The garage advised they cleaned the fuel sensor and cleared the codes, all would be fine

Fast forward another 2 weeks the amber light comes back on, so back to the garage

Print out this time reads

P008B-00 Low Pressure Fuel System Pressure too high 

P2096-00 Post Catalyst Fuel Trim System too lean bank 1

U2100-00 Accessory Protocol Interface Module, initial configuration not complete 

None of those codes are usually caused by a low battery voltage.

Have you checked the battery SOC ?  I think you will find it is probably around 70%