New problem - heater, tech stream and dash interface

Ok, I thought I was in the clear after seemingly getting my battery problems behind me, but I have still not successfully made a real point a to b trip in a Prius yet... Tried today to drive to the closest local town, but it was about 40 degrees, so I turned the heater on. When I got this car, the combination meter was bad and then I had to replace the dash monitor with one from my parts car. The original one worked for a while, and I saw how it was set up with all the options for display - it was awesome. The one I replaced it with was pretty std, just has the 4 buttons, and limited on the info, so that is one thing, don’t even know why I mentioned it, but I was able to get into the climate settings and set the temp up high enough that it should have sent the proper request for hot air to be sent, you know, the actuator doors to be opened and fans and valves and such. Anyway no hot air. Unfortunately, I was on a bad stretch of 2 lane road with no good place to turn around. So my round trip was probably 8 miles, farther than I should have taken it, without knowing if it was overheating, like a with a thermostat not opening, or something. There was no light or warning that it was, just made me uncomfortable not knowing. Anyway, when I got home, I opened the hood, and nothing smelled hot , nothing even felt hot, which seemed weird, though I don’t remember touching the hoses, (which would have made the most sense)... I did open the radiator cap, and it was fully pressurized, as it it sprayed a fairly good amount of antifreeze around when I opened it. But, oddly, the fluid that got on my hand wasn’t excessively hot at all. Kind of weird for the kind of pressure...and something similar had happened the other day when just drove it around the “block”, not even long enough to get up to operating temp, but I checked the fluid, and it was pressurized just like today...so I was trying to research some other posts before I put this up, and I saw one talking about 3 different conditions to check to determine what a P1121 code really meant, (I haven’t checked my codes yet, waiting for my old laptop to charge up), but it said that with Techstream, you can watch it while it heats up, so you can identify what condition you are really dealing with... how do you use Techstream like that? I haven’t seen how to do that kind of dynamic testing, can someone lend me a hand in understanding that, as well, please? Thanks very much!

 

Wow

 

In retrospect, I can totally see your point that only an idiot would take off a hot radiator cap. However, I must have failed to convey that it was not at all hot either time, and I had thought the pressure was the pump had built up a small amount of pressure from not being able to properly flow through the entire system, as in a stuck thermostat. I have since re-thought that, but never mind, I’ll figure it out. Thanks to those who have made a good faith attempt to be helpful.

 

Thank you. I was able to view the live data aspect of Techstream, so that was very helpful. Before that, the heater did start working, and one of the codes that came up was a stuck valve, forget right now which one, but once I cleared it, it did not come back. I don’t have complete confidence that it won’t, but I imagine it can be explained by the car sitting for as long as it has. I intend to replace the valve, and ease into using the vehicle regularly, in case there are other latent problems waiting to rear their head, but happy at the moment, at least.

 

Thanks, I will try that.