FLYCT

We're on our 3rd hybrid. Our new RX450h traction battery cooling fan under the back seat seems to run consistently after the car is driven for a few minutes.

Our previous Prius and CT200h did not exhibit this.

Is this typical of the 450h?

lexus114

well, i wish i could help but i dont have the 450h.....

mcomer

Are you sure you are hearing the battery fans and not the seat ventilating fans?
The seats have two (2) fans each and they sound quite loud near the rear seat
floor. Try turning them off as well as the HVAC and then listen for your fan noise.

FLYCT

mcomer,

BINGO! It was the driver seat ventilating fan noise I was hearing, not the traction battery fan.

THANK YOU!!!!

mcomer

Glad it was so easy. To enhance the effect of the seat coolers, turn the vent on the back of
the center console off by rolling the valve wheel down. Remember to turn it back on when
using the back seats!

tempestv8

I had a quick look underneath the front seats and can't see any ducting that might serve as a conduit for cold air coming from the chiller unit of the airconditioning system. There was none.

Then I found a youtube video that shows how the ventilated front seats actually get their air source: So basically it's just drawing ambient temperature from the floor area. Definitely not chilled air from the airconditioning system.

Back on topic, the traction battery does seem to have cooling fans. Part number is G923048040

tempestv8

How audible should the traction battery cooling fans be? Today, I drove around with the HVAC turned off, and I noticed a fan noise coming out from the vents under the floor of the 2nd row seats.

Should these fans be fairly hushed? Mine was clearly audible.

I am now wondering if there is a way of cleaning these fans. I have seen lots of Prius hybrid battery fan cleaning videos on Youtube but none for the RX450h.

Looking at the diagram, these fans seem to be located behind the plastic grille bezels.

Droid13

Interesting diagram!

But as I see it the blowers are not behind the small plastic grills. The service port is shown at the left, and it's on the left inside the car too, so that suggests the blowers are behind the battery pack and instead of blowing air onto the packs, probably act as exhaust fans instead, maybe blowing the air into the trunk area somewhere (or they do blow air onto the pack, but exit via the grills under the rear seat). This would be a lot quieter setup. I've never heard the battery fans in my car. I've occasionally heard mysterious fan noises, and its taken me a couple shakes of my noggin to realize it's the front seat cooling fans that I forgot were on.

Ssd108

I purchased a used 2010 HiHy here in TX couple of months ago. It has 160k miles and I wanted to try to recondition the Hybrid Traction battery to eek out few extra years from its life. Purchased the deluxe reconditioning package from Hybrid Automotive folks and tried to do the 3 cycle (charge / discharge) reconditioning. The cooling fans are supposed to be running all the time when charging or discharging using their equipment. When installing the harness we had verified that the cooling fans were indeed running when the charger was connected.

However, when doing the 2nd charge cycle with the car sitting in my quiet garage, I tried my best to confirm that the cooling fans were running. Neither could I hear any sound at all - nor could I confirm any air flow movement at the intake vents below the 2nd row seats. Also no indication of any air movement at the outlet area, which in my vehicle is on the body panel just behind the right passenger 2nd row seat.

Unable to confirm if the cooling fans were running I aborted the reconditioning process

However, since then I have purchased a Mini VCI Cable and corresponding software (TIS) using which I can at least check various battery parameters. When I attempt the reconditioning again, I will periodically disconnect the charger / dis-charger and check the battery temperatures to make sure it is not going too high - though first I will need to find out how high is too high

I posted on toyotanation and priuschat forums if anyone having the HiHy vehicle could confirm if they are able to hear the cooling fans running or able to confirm any air movement at the vents - but got no response. If any here having either a RX400h or RX450h confirm this - that would be most appreciated.

Hare Krishna!

tempestv8

I had to look up with a HiHy is. Eventually the penny dropped - Highlander Hybrid. Right, OK, now I understand what you are asking about.

Can't tell you whether the HiHy makes any fan noises at all, as there are no HiHy models sold in Australia, but on the RX450h whenever the cooling fans for the battery packs come on, it's subtle but definitely audible.

I didn't know that there was a Hybrid reconditioning package, will have to investigate that.

tempestv8

After some research, I think I'll just let my traction battery wear itself out and, if I were living in the USA, I'd compare the replacement cost of a new battery from Lexus vs one from this company: https://greentecauto.com/product-tag/lexus-rx-450h

In Australia, Toyota offer a AUD$500 rebate if you return the old battery to them when buying a new traction battery. I haven't priced one up yet, but it's probably north of AUD$4K.

riredale

I travel with a big long-haired black dog around with me during my day trips. I have a folded-up blanket on the rear seat to protect it from claws, but I wonder just how much dog hair has been sucked through the vent grilles already. I would imagine there is a temperature sensor for the battery pack that is monitored, so I'll eventually find out when it's time to vacuum out the traction battery.

BraveHelios

Hey all,

Does anyone know if these fans can be accessed and cleaned out and how to do so?

Thanks!

Clutchless

There are several YouTube videos that show how to clean Toyota hybrid cooling fans and related ductwork. Apparently there may be a filter at the air intake on the rear floor. The filter reduces the need to clean the fan and ducts. Just replace the filter.if you have one.
See this old thread which has links to PDFs with more information, if the links still work.

https://www.clublexus.com/forums/hyb...rear-seat.html

​​​​​​https://www.clublexus.com/forums/hyb...ng-manual.html

​​​​​​https://www.clublexus.com/forums/hyb...an-filter.html

FYI on my 2011 Lexus HS250h sedan I cleaned out the hybrid battery cooling fan ductwork and fan after removing the back seat. The duct work was not difficult to take apart.
I was able to unbolt the fan (3 bolts) one of which was accessed from the trunk, and clean a fine layer of dust from everything.