The manual confirmed one should pull over and stop. Anyway we got bored quickly with that! So we went to carry on. But upon attempting to move off Parking brake would not release!
Now we could see at least there was a problem.
Found the emergency parking release lever in boot. It took one wussy pull and one strong pull accompanied with clunk and slight rolling of car forward to release it.
Drove to Lidl Stillorgan. No parking brake. So hills interesting. No excitement though. Parked in gear and wheels to kerb. At shops and at home. Parking brake remained in error and refused to do anything. Red light on brake flashing.
The internet has various causes detailed. From EPB unit replace or motor replace 600 or 400 euros to . . Cable seized. Or fuse. Or low battery. Found fuse well hidden under passenger seat (Take out the drawer under the passenger seat. The white 25A fuse is the parking brake one.). Taking that out, examining and replacing has changed behaviour from parking brake not doing anything to it trying to go on but failing. Can hear motor weakly. So wethinks cold weather and battery.
Occam's razor. It's always most likely to be a simple problem!
The fuses under drawer under passenger seat.
Thanks to the internet for advice!
But FIRST check it is not just low battery.
We need to fix up the internet a bit.