Some HV battery questions

On warm days the HV cooling fan will run and can be heard. If the fan runs on high for long periods, it is an indicator that the HV battery is generating more heat than it should.

There are two independent coolant loops: Inverter and Engine. Both use Toyota type SSL coolant (about a gallon each). Toyota says to drain/refill (do NOT flush) each at 100k miles and each 50k miles thereafter. The job has some DIY issues as it can be difficult to get air out of each cooling system.

No, there was a recall on the electric inverter coolant pump in the US.

It has been suggested that the Toyota Type WS ATF Be drained and refilled at 60k mile intervals (The Tranny is NOT sealed. I suggest that the first Exchange be done at 30k miles). It is a reasonable DIY job and you can search this site for directions. You will need 4 quarts of the ATF from a dealer and two sealing washers for the fill and drain bolts. My dealer in Connecticut charges $100 for the job.

JeffD

 

It is good to clean the battery fan, an easy project:
Fur and dirt causing major battery problems | PriusChat
If you can hear the battery fan, the battery is getting too hot and wants to be cooled. Run the AC as that keeps the battery cooler too.

Yes, replace inverter coolant if it looks at all cloudy. It too is a DIY. This link has more than just the change:
100K maint - 4
Your pump should not make more than a somewhat faint whine. There may be air your system, or it may be about to go, like so many of the ones in GenII. There should be good turbulence in the reservoir when the pump is on.

Yes, replace the transaxle fluid with 4 qts of Toyota ATF-WS. Easy to do if you can get under the car, just drain and fill. Endless discussion about it here. For ex:
Transmission Fluid Change? | PriusChat

 

Any time that it's warm and you've driven for 30 min or more then you'll probably be able to hear it. Normally it shouldn't be loud enough to hear from the drivers seat. But if you stop (leaving the car in ready mode) and go around to the rear seat, you can put your ear next to the vent and hear it whispering away.

 

There is a recall on the inverter pump in the UK "even with the pump showing no problems" along with a steering shaft problem so get your dealer to recheck the situation. I had my car done a few months ago.
Changing the pump also requires them to change the fluid "Toyota instructions with pump change" so you should get the fluid changed FOC along with the pump.

Make it clear to the dealer that you have read the Toyota instructions on line for the pump and fluid change or they will just clamp off the hoses and leave the old fluid in there, selling the fluid that Toyota supply with the pump to make extra profit.

Be careful when changing the transmission fluid as the US quarts are smaller than the UK quarts and are actually much closer to a litre than two pints, so buy 4ltrs. Four quarts would grossly overfill the transmission.

The A/C will discharge the HV battery faster when used as it runs directly from the battery so when in use the windows should be closed to allow the cold air to be drawn in to the battery. Leaving the windows open and using the A/C could actually increase the HV battery temperature as it is working harder to run the A/C and taking in air at around 28 C.

John (Britprius)

 

If you intend changing the engine coolant and if it has not already done you should. Check on the capacity in the hand book if you do not have one let me know and I will check for you.

Again the quantity is much smaller than the US not only for the reasons in my previous post, bout the UK Prius does not have a coolant thermos bottle, valve system, and pump that the US version does. This makes the capacity much smaller, and the system is simpler to bleed air from.

John (Britprius)

 

Turn the back windows off with the child switch on the front door rest. Then tell them your waiting for repairs.

John (Britprius)

 

Your backwards there aren't you?

Trans takes 4 US quarts. Done mine twice.

4 liters would grossly overfill the trans.

US Quart 32 ounces
UK Liter 35.1

 

Now I'm not being rude here but maybe they are opening the window because the car smells bad. And they do not want to be rude to you and mention it. Common complaint here on this site about stinky ac.

If the AC e-coil box under the dash is not serviced/cleaned regularly the car will smell moldy. Gym socks is the most quoted smell on this site.

Some people do not notice it others smell it instantly. You may not notice it. Do you smoke also in the car?

If I routinely transported people in my car I would keep up on that service.

 

Hi Ed. Britprius is referring to the UK quarter gallon, which is about 1.15 litres. Yes 4 litres is a little too much, but 4 UK quarts is even more. OP probably wont have US quarts available in the UK, so next best thing is to buy 4L.

 

I'd be tempted to check and double check the 12v battery too.

In my taxi experience I think I heard the HV battery fan about 2 or 3 times. I think it's harder to hear on a RHD car than the LHD because of where the vent is. It sounds like an old fashioned hair dryer. Also, don't be alarmed at the horrific noise from the front when you run the a/c on high on a hot day. Sounds like a buzzing or electrical transformer noise. It's just the compressor. Are you mistaking that for your inverter pump?


And to our American friends - a/c is fairly new in the UK (last 20 years) on lower end cars and many erm how do I say this politely, older or more mature people don't quite 'get' it. It used to drive me nuts on a hot day when you'd have the car nice and cold and some old lady would get it and immediately lower their window!?! I gave up telling them in the end.

 

No the UK quart has 20% more volume than a US quart so putting in 4 UK quarts would be a 20% overfill.

US Quart 32 ozs, UK ltr 35.1 ozs, UK Quart 40 ozs

Filling with 4 UK quarts would be an overfill of exactly 1 US quart. The reason I suggested buying 4 ltrs and not
4 quarts.

John (Britprius)

 

Be aware have the regassing done at the dealers or make sure the workshop it is done at uses the correct ND11 oil. Also make sure the equipment used is not used on non hybrid cars.

An electrical ground fault in the compressor can very easily be caused by contaminating the oil in the A/C system with standard PAG oil. Your looking at towards £1000 for a new compressor fitted and will not be covered by guarantee.

John (Britptius)

 

That is indeed the brake pressure pump working.

John (Britprius)