Changing engine coolant

The little 12v battery is an AGM (Absorbed Glass Mat) lead acid battery.

DoctorD

 

you are correct my mistake.

 

If you can change your spark plugs and battery yourself, you should have the skill set to change coolant. You just need to have the right equipment to stay safe under your car.

 

Just curious, is it necessary to pull the wipers and their motors on gen 2, to get spark plug access? 3rd gen is just nuts.

 

gen3 just nuts

 

It is not necessary assuming you have an appropriate length extension for your 3/8" socket wrench.

 

No, I did loosen the big harness and moved it so to get to #4. The first three were easy. The last one just a thing in the way.

You can do it, not too bad. Just remember to do it on a cold engine.


LG G3 T-MOBILE phone ☎

 

Patrick,

First off, thanks for being so generous with your time in helping everyone.

I have a '08 prius that I recently changed the engine coolant in. Car has been running perfectly following similar instructions (I did not short the CHS relay). No error codes or over heating issues. However, I used to hear the CHRS pump after turning the car on and / or off. I do not hear it run (maybe it has the proper amount of coolant not to be noisey any more?).

Do I have reason to believe that the pump isn't running any more and will gen 2 detect if it is malfunctioning?

 

If the coolant heat recovery system pump is not running or the coolant system is clogged, then DTC P1150 normally would be logged by the engine ECU. The ECU monitors the sensor at the CHRS canister output, tracking the coolant temperature as coolant is pumped out of the CHRS canister. The sensor is looking for a big change in temperature which shows that coolant is flowing out of the canister. If it does not see this temperature change then the ECU assumes the pump is not working and logs the DTC.

 

If it logs such an error will it have a "check engine" light (or something to that effect) on?

 

Yes MIL or check engine light will light. P1150 fault only has to happen once for MIL to turn on.

 

Sounds like my initial theory is not far off --- may be working "better" in comparison to the previous coolant level which may have been minimal to work without overheating. Before it had a clear high(ish) pitch tone upon start up and shut down. Now it is silent hence the concern!

Thanks for the feedback it does help ease the mind!

 

This procedure worked perfectly to fill the thermo tank (CHRS) in place of the scan tool procedure in my Bentley Repair and Maintenance Manual. While using multi-meter to monitor amps it took several 30 second runs to get up to about 4 amps. Did this while following the procedure in the manual (opening and closing the bleed screw) and continuously expelling air out of the radiator neck by squeezing the right side radiator hose and topping up coolant in the radiator. Did this until it would take no more coolant (took about 6.5-7 qts). Skipped active test mode, but drove it hwy speed for short distance. Let sit over night. Added a few ounces of coolant to radiator and overflow reservoir. Drove another short trip. Let cool, added a few more ounces of coolant and continued to monitor coolant level for a week or so - needed none. A couple hundred miles later all is well. No fancy tools needed, but the key is to ensure the pump requires about 4 amps to run, all air is expelled out of the radiator, and it will take no more coolant because all that drained was replaced. Note: I did use air pressure through the radiator to force out more coolant out while draining. Thanks to all who contributed to this thread, which was invaluable to complete this job and save a few hundred of my fiat currency reserves.

 

Anyone know if the 2016 has the same issue or procedure?

 

There isn't a coolant thermos on 4th gen, or 3rd.

 

excellent.

 

I really, really wish I had found this thread two days ago... now I'm waiting for amazon to deiver the nut extractor while my car is in pieces in the driveway...

 

Yes, nobody ever mentions those two nuts....

 

G'day Patrick et al,
Do y'all recall which sizes (inner diameter = ID) of tubing or hoses are best for the coolant drains? I would really like to avoid making a mess when I drain the coolant from each loop.
Pinback

 

The drain spigots are readily accessible: check with a caliper and/or some assorted tube diameters, in advance.