2014 Transit 350 TDCi Fault Codes On Start Up

[chris2005]

Hi All

I have a 2014 transit which is bringing the fault codes below at startup if the van is left a few hours

U0121 ( lost comm with anti lock brake system)
U0140 ( lost comm with body control module )
U0001 ( high Speed can bus )

If the van is started and stopped after few minutes no fault codes show

Van is driving OK apart from these codes that keep showing

The back battery was showing 11.9 volts if left for a few hours so I replaced that one but it made no difference, front battery is showing 12.4V