Here's the background I've been riding at highway speeds for about an hour. The yellow triangle caution light comes on on the left side of my instrument cluster. Almost immediately a second yellow caution triangle lights up next to my front tire monitor on the computer screen.

I pulled over shut down and inspected both the front and rear tire. Finding no nails or cuts I got out my tire pressure gauge and found I had 2.5 Bars in the front and 2.8 in the rear.

On restart I had no readings for either front or back even after travelling down the road. I road home and rechecked the air pressure with my digital reader and got the same results.

An hour later everything was back to normal with the front display coming on upon start up and the rear after travelling a short distance.

What happened?

Do the sending units in the tire run on battery (watch size) and could they be due to be replaced. The bike is a 2008 F650GS Twin.