cooling performance of hybrid battery is low

[Quay]

Hi there, I've got this message pop up on my Lexus IS300H, 2014. I've searched all over the internet and forums but can't find anyone with the same issue so seems like an uncommon issue amongst Lexus. However, there are plenty of posts for Prius', where most owners clean out the Hybrid fan which is located below the seat. Has anyone experienced this issue with their Lexus and any advice for fixing would be much appreciated? The error message is literally 'cooling performance of hybrid Battery is low'. I do use the car very regularly, about 70 miles a day on average.

[Hangie]

I would start from checking vents inlets. In GS they are on the sides of rear seats. I assume IS is the same. Check if they are clean and nothing stuck inside.

You can also check for the fan noise to check if fan is starting.

[Quay]

Thanks, I’ve checked and vacuumed the vents but struggling to find the location of the fan? Any ideas where it is? Do you know where it is in the GS?

[Farqui]

On my mk3 GS the fan is under the rear parcel shelf and is easily accessible via the boot trim.

[Britprius]

The cooling fan will be close to or even fitted on the Battery. The most common reason for the fan to be low on performance is the carriage of pets "particularly hairy dogs" on the back seat. The fan acts like a vacuum cleaner in the area of the intake vent. Once the fan is removed, and cleaned make sure it spins freely as partial seizure of the oiled brass bearing is also possible.

To lubricate the bearing "if required" on the back of the fan assembly there is a round aluminium disc about 4 inches in dia. In the middle of the disc is a paper sticker. Remove this to get access to the bearing. Use a very light oil such as 3in1. replace the sticker with a piece of tape to stop dirt entry.

John.

[steve2006]

The ducting from the hybrid Battery to the fan at the top of the picture is shown below to give you an idea of what you are looking for.

[Quay]

Thanks all! Your input has been really helpful. I found the fan in the right side of the boot just above the wheel arch. I’ve given it a good clean but it didn’t seem too dusty when I found it as you can see in the pics. Moved freely too. We don’t actually have any pets so wasn’t expecting it to be too dirty. Will take it for a long drive later in the hope this warning message on the dash disappears as it hasn’t yet. Will update again shortly

[Quay]

FIXED! Following the cleaning of the vent and fan, I reset the dash warning message using a fairly cheap diagnostic machine and it’s been several days so far that it hasn’t reappeared. So the message doesn’t go off itself, it must be deleted. Thanks all!

[ColinBarber]

Excellent 🙂

FYI - the warning message would have probably disappeared after three journeys without issue - that is the norm.

[Alan100]

Hello Quay,

When you say it was just above the  wheel arch did you have to remove  much of the trim to access it? Do you have pictures of were I should look? Thank you 

[Quay]

Hi there, no didn’t have to remove too much although fiddly. Here’s the location just above the arch. Hope this helps.

[Alan100]

Hi Quay,

I found the fan with the help of your picture, it looks a complex for me to do myself,did you have much trouble? Might have to go to the main dealer?

Thanks for your help Alan 

[Quay]

Hi Alan, it was fiddly and did take a little while to get to but do-able.

I guess you could get some quotes from some other garages as they may be far cheaper than main dealer. Worth getting a comparison.

Quay

[claudiocristo]

Hi there , 

Had the same problem on my IS300 H 2014'. Followed all of your comments i managed to get is sorted out as well. It was a bit tricky to find , but it turned up well. 

The fan is located in the boot, on the right hand side above the wheel arch. 

Firstly you need to plug out the plastic pins that hold in the material onto the bodywork ( no need to remove it completely , just to have accesss to the fan ) , after you get access to the fan , remove it from the bolts that hold it in on the bodywork ( should be 3 long screws )  ADVICE : Before performing this , disconnect the car Battery so no current flows through the circuits. Also , do not unplug the air fan from it's wires !! Just simply unscrew the bolts that hold it together and the air fan should come out into two pieces, that way you do not have to take it out completely and the access is good. 

For the ones thinking it's a big job or need to consult a dealer, absolutely no need. You indeed  need to be careful on what you do , but with gentle care and no wires disconnected , you should be fine. The dirt from the fan could be easily removed with a new soft paint brush if you do it properly and gently from the outside of the fan radius , press a bit harder first , the dust is stuck properly to the vents - it will get a bit dusty in the boot by doing this , so get a cloth and cover the other intake from the flat black plastic tube that goes down underneath the cover towards the batteries , you do not want dirt to get in there.

 

I will upload some picz i took so you lot kinda see what i done if you are confused. 

P.S - clean the dust on the air intake for the fan as well , located on the right hand side from the back seats between the seat and the door. 

The warning message disappeared instantly after plugged the Battery back in and took it for a spin. 

 

Wish you all luck 🙂

 

 

 

 

 

Pictures were made after cleaning the fan ( it was nearly black and dusty )