Hello- A question about the coolant level of my gen 2. I've been getting an intermittent Check Engine light. I checked the coolant overflow container and with engine cold, it's about an inch below the top of container. I don't see a fill line? Question 1: should I top off the coolant to the top of the rectangular overflow container? Question 2: I've read Prius coolant systems are complex. Can I just open the overflow and top off? Or are there other steps involved? Question 3: Do I use the same coolant for the battery as for the engine? Thanks
0. check engine light usually is emissions related, can be caused by p1121 coolant valve or a bad catalytic converter. I would suspect the bad catalytic converter would be more of an intermittent thing. Best to get codes before doing the repairs. It could also be as simple as a bad gas cap 1. You should top off the coolant at the radiator (where you remove the radiator cap when the car is cool), and fill the overflow container afterwards 2. They are not very complex if you are not draining and refilling. To top off it's straight forward. 3. The battery does not use coolant. The proper coolant to use is the pink super long life coolant from Toyota, or an equivalent product from the aftermarket (usually label pink asian fluid)
Check engine might be something else than coolant. Do you have an OBD2 reader? Always Top off coolant when cold. If not, this is a good place: Hybrid Mechanic / Auto Repair - Electric Ave Silver Lake
BUT....if the overflow bottle is already near the top when COLD, then a lack of coolant is NOT the problem. It should not be that high.......and might not be looking at the right container for coolant.
Coolant level in the overflow tank is meaningless on this car. Could be full and rad low. Take the plastic cover off the top of the rad the radiator cap is under there. If the coolant is low in the rad you probably have a leak. Engine water pump is first guess. But who knows you never posted the cars mileage on a car forum post. And coolant in the battery don’t even know what that means. Intermittent check engine is probably your out of engine oil.
I don’t know but it does not reflect what’s in the rad for some reason. Probably because of the CHRS system I would imagine. Probably why the euro/japan version abandoned it. I like to train people to actually look in the rad itself so they are used to looking at levels. Takes all of 10 seconds. Cannot lose. Pretty complicated engine cooling loop compared to a regular car. Near impossible to drain the engine and rad and recover without air lock without outboard cycling the bottle. Many a dealer has f’ed that up based in what I have in the last 13 years.
