Dad 45

[creggan]

Hi
I have a m reg daf 45 ( yes it's a horsebox) lol
Whilst using it at the weekend their was a very quiet beep noise which then became a constant buzz , like the air brake buzzer but a lot quieter . All the gauges and lights were as they should be , engine has water and oil and cab is locked down but the buzz won't stop.
Any ideas what it could be trying to warn me about please
Thanks sara

[Willy Nilly]

Any lights on the dash? Do you have the manual?

[creggan]

No dash lights