Good Morning All, My 2007 had the 3 way coolant Control Valve replaced around May '24 no CEL (corrected P1121) As soon as the weather got cold in the North East around November 1 I began to get a P1116, Replaced the coolant Temperature sensor, code stayed clear for about a week. This past Thursday night Did a coolant burp just in case the Thermos was airbound and too see if the graphs provided by Tech info matched what they were supposed to look like. I did a data record and used techstream to plot the graph. My graph looks like the Coolant Temp at the outlet is tracking with the Coolant Temp as expected but there is definitely something off with the water flow valve and the Direction Valve one . Is it possible that there was a possible plumbing issue when the 3 way valve was replaced is it possible from the graph that the hoses were connected wrong or would these errors shown themselves much sooner? I was unable to get Techstream to a state where it would manually let me run the coolant control valve to fill the coolant storage tank as an extra measure just in case it was airbound. And when the coolant was replaced in May an air lift system was not used. I am just confused as to why this error would creep up so many months later. I did run the heat for a lot of drives in may and I did hear air bubbles back then when I shut the car off but I would just keep adding coolant to the coolant overflow tank (under near the plastic guard by the front bumper not the Inverter coolant reservoir) to ensure the level was at full. Any ideas? After this bleed procedure last Thursday the coolant level in my coolant funnel was slightly higher and I expect that was because of coolant expanding. I was unable to see if there were airbubbles during that procedure because I was in the car holding the pedal and just looking for the temp and voltage changes to happen which they appeared to be correct. Heat comes on as expected and gets real hot about 10 minutes into my drive. I am in a state that does emissions so although I can clear the code and get the monitors ready I would like to chase this ghost Incase another CEL condition happens and I don't write it off as being the pesky P1116. I hope I provided enough information. Thank you in advance
I'll have to read the rest of all this in a minute but to make the coolant control valve hoses be connected incorrectly you would be able to look down at the coolant control valve with your glasses off even and noticed that the hoses are bent incorrectly and something doesn't look up to Toyota or manufacture standard this hose is bent way too much and looks like it should be there there's only three One feed from the bottom and two from the side even if you put the two from the side on incorrectly they don't look right that's on purpose. I thought one of these codes look like the coolant heat storage tank That's a pump and a sensor and a thermos bottle The thermos bottle's not damaged it's the pump or the sensor or whatever controls the pump and reads the sensor That's all there is.
Also this was not explicitly mentioned in the tech guide I was following but I have seen a YouTube video where the person shows you how to jump the pump with a multimeter to purge air from the thermos I did not do this proceedure. This fault occurs as soon as the car is started cold start so I would imagine that the coolant temp sensor does not like how much the coolant has cooled off over night since the last start. The pump definitely runs because I hear it whirring during shutdown and start up
Yeah I've got a '07 car that's done the same thing for a couple years I've got a couple of pumps a couple of temp sensors and I was about to tackle that nonsense waiting for that to happen when it got cold It got cold and freezing and the car's been working absolutely stellar has it thrown the code for the 11:21 I can see the pump the fender liner is ripped and everything seems to work at startup and I think it comes on 5 hours after shut down to sample or something along those lines. And then when you come out and start in the morning of course it pumps and does its business.
I would suggest that you use Techstream to graph that same data during a cold start and see what you get. Go ignition ON - not ready (foot off the brake & power button x2). Turn off the HVAC fan - system. Setup your scantool to record your data. Now go ready, the CHS pump will run about 5 seconds before the ICE starts. Both the water outlet and ECT temperatures should increase from ambient by around 100°F. Here's a capture from my 2006 on a cold start. Posted via the PriusChat mobile app.
I have not yet had the chance to do a cold start test but, I do have cold start freeze frame data that triggered the CEL, looks like it triggered with the outlet valve sensor reading at about 90F . I do take shorter trips and I don't know that I get to full temp beyond 185 often I uploaded the screen shots from techstream below
That's the sensor on the bottom of the tank screwed into the plastic or the business that goes to and from the tank so I guess that's the outlet and the inlet I don't think there is a tempt sensor on the inlet or on one side that would be the same as what's coming from the engine I guess the outlets are measures the water coming out of the thermos after it's been sitting all night or what have you? So what would that mean The sensor is bad or the coolant is getting too cold and not making the sensor temperature high enough striking a code weird how are you going to make the coolant stay any hotter? Or what needs to be done here?
That's my question as well, there is a sensor at the CHST outlet that I changed last month, and there is infact a coolant temp sensor on the engine block as well but that would throw a different code entirely. To my understanding the Thermos is supposed to be able to keep the coolant at 180 for up to 3 days. I don't know what the threshold is to set that code. I did manually jump that water pump yesterday for 10-15 seconds at a time to see if I can burp any air in it. There was no such air. Over the summer after a coolant dump and 3 way valve replacement (P1121) I did notice some rust in certain parts of the radiator system, and for a few Starts and restarts I did I have air bubbles but I kept topping off the reserve and running the heat full blast and it never caused a code. I did not refill with an air lift system. I know I can just wipe the code and ready the monitors for NYS inspection but I'd rather get this resolved because I don't want to mask a more serious Fault if it occurs with the CEL already on
last time when I have the P1116 error code was due to a missing relay in the relay holder just above the ignition coils. My Prius was hacked by the previous owner (bypassed the 3-way coolant valve) Have you tried activating the water pump using techstream? In my case the pump wasn't working at all and immediately got the P1116 but you mentioned that it is working on yours on startup and shutdown? ff at 6:58
The relay is there and I manually Jumped the pump yesterday to Burp, and also hear it run at start and shutdown. I will check out the video you uploaded now. Also even when the CEL is first turned on at the morning cold start the pump is infact running
As I am reading in another thread from '09 "Just to state that this is the 'coolant heat storage tank sensor', i.e. the thermos. The sensor is supposed to tell the computer that it's getting hot coolant back from the thermos. The code is logged if there is less than 1 degree Celsius increase after opening the valve, or if the engine coolant sensor reads more than 25 degrees C higher than the thermos outlet temperature sensor. If this doesn't happen, chances are pretty good that the sensor has stopped working. It can also indicate that the coolant isn't flowing properly due to a blockage. Since I can plainly see by my data that I posted above it looks like the Coolant Outlet from the Thermos is only 72 degrees F and the Engine sensor is Registering 153. What would cause this discrepancy? Is it that the Tank isn't keeping the fluid hot enough due to air, or some sort of tank failure?
Do the cold start data capture as described. Need to see what the entire system is doing. In particular do the 2 coolant sensors read the same (ambient) temperature after sitting all night? The freezeframe suggests that the CHS system works, ECT initial of 65° going to 153°. Have to wonder if all coolant hoses are connected to the proper positions. Posted via the PriusChat mobile app.
Yep they aren't routed correctly, white dot hose is on the bottom and should be on the top,, just compared with another Prius as well. If I clamp them off then remove will I get enough air to warrant another coolant burp or will I be ok if there is minimal coolant loss? Proper routing posted below for future members
