Red triangle light and engine symbol came on

This evening while I was following my husband on his lawn mower to the car wash to wash his lawn mower, the red triangle light and the yellow engine light came on. Also a pale red car and a ( looks like a knife) through it all came on. I was almost home. I'm thinking it came on because I was behind my husband making sure he didn't get run over and so I was basically not using the gas pedal. I'm just wondering if this is a major problem or I just need to drive the car at a normal speed. It's a 2005 Prius. Thanks, Einnoc.

 

I realize this sounds silly, but it's the truth. I'm thinking because I was following him at such a slow pace I wasn't using the pedal much and maybe the battery was low. I had been gone all week and then I came home to help him and by driving at such a minimal speed, I somehow took power away from the battery.

Checked this morning and it was still lit up. I'm afraid to drive it to the dealer, and maybe I should have it towed, but tho't I'd get on here first. This is my first time in a long time to have to deal with a red light issue.

 

The last time I had the red light come on I was at a car wash with a rail to go into it and the guy last minute put his hand inside the car and put it in neutral and by the time I got thru' the light was on and it was scary. i can't remember what was done at that time, but I drove it to my mechanic and it was ok.

Thanks for your time. I'll let you know what they say if you are interested.

 

Ok. I went to my mechanic and he has a new scanner. They rebooted the computers (4). It took about and hour and they finally started talking to each other. It looks ok for now. If it does it again it will probably be time for me to get a new battery. I'm thinking it's going to last a long time. It probably didn't like me idling behind my husband. His lawn mower is clean tho'. Have a great weekend and thanks for the reply.