I had a 70 plate DAF rigid at the beginning of the week which threw up an amber TPMS warning for the O/S rear axil, but on inspection the tyres appeared to be fine.
I didn’t know that tpms was a feature of DAFs and when I got back to the office they said they knew about it and it was a regular occurrence, but there wasn’t any tpms fitted on that truck. However I suspect that they were BS’ing me about this just just to get the truck out of the yard.
Daf has had tpms for years. Uses abs sensor to measure rotations of the wheel so errors are common. Use the dial to go into menu and tpms and calibrate it to get rid of the warning after checking tyres obviously.
Use of abs sensor is the cheapest way to measure tyre pressure and every vehicle I’ve had with that type throws up errors when it detects a wheel spinning at a different rate to the other. Even the vehicles fitted with a tail pressure sensors are crap as well.
Waste of time system check tyre for inflation regularly and you know when you have a flat tyre while driving unless your an imbecile like some of the idiots that continue driving unaware they have a flat tyre. 
Second the above. Experienced it on a 19 plate when I got it on days during lockdown. Took it into workshop a few times in first week who checked tyre pressures and everything was OK. Noticed it tended to happen when the load was more heavy on one side than the other at the front, eventually just ignored it. I carry around a tyre pressure gauge so if I was unsure I’d just check. Never found any instance where a warning it gave was actually because of low tyre pressure.