Engine Systems Fault - worth fixing?

[cmxpress]

My old Focus Zetec 07-reg recently started showing a red light with the message "engine systems fault" and going into limp mode. I've run a diagnostic and come up with errors in the following areas:
 

• P0299 - Turbocharger/Supercharger Underboost - Signal above maximum threshold
• P0234 - Turbo/Super Charger Overboost Condition - Signal below min threshold
• P0335 - CKP Sensor A Circuit - Signal above max threshold
• P0704 - Clutch switch input circuit malfunction - Invalid signal
• P0380 - Glowplug control circuit - Signal above max threshold
• P0490 - Exhaust Gas Recirculation Control Circuit High - above threshold
• P042F - EGR Control Stuck Closed - above threshold

These all seemed to have arisen after the car was sat on the drive for about 6 months in Lockdown.  The battery was a bit low, and it took a few starts to get going, but has been ok since then.  I checked the battery terminals and was getting a low signal at first,  but a bit of a drive seems to have charged the battery a little. The car had a new Turbo about 3 years ago, so I'm not really expecting that to be an issue.

wondered if any these fault indicated a more serious problem, and if so what it *could* be.  Didn't really want to Shell a load out at a garage if it's going to cost more than another car to fix as money is a bit tight right now.

I've attached the full diagnostic report here.  If anyone could help with some advice that would be much appreciated!

 

2021-05-11.txt

[StephenFord]

I'll be the first to advise. You need to give the battery a proper charge with a charger. Until it's punching out at least 12.8v, you'll never have a baseline for the faults as so many will be caused by a low battery output. (car will start with less, but it won't be on all systems go until full charge) Taking her 'a drive' won't really cut it I'm afraid...

[cmxpress]

@StephenFord - thanks for that, I'll give her a good charge then try her again.