longne

Greetings,

I just got my wife an 06 400h and I have started to notice an unusual noise coming from, what sounds, like beneath the passenger rear seat. It sounds kind of like a playing card in a bicycle spoke. It doesn't do it all the time and it seems to get louder if I go over a bump. I speeds up and slows down with the vehicle, but will continue to sound even when the vehicle stops.

At first I thought maybe it was either a bad CV joint or one of those wear scrubbers on a brake pad. Neither seems to be the case as the brakes look okay and the CV boots look fine, plus it does it when the car is completely stopped.

I've been working on cars for over 25 years, but my hybrid knowledge is limited. I'd rather have some idea of what I'm dealing with before I start messing around with stuff.

I have tried searching, but haven't found anything that looks similar. Any advise or ideas would be greatly appreciated.

Thanks,
Nathan

spacecraft

Do you mean also with the ICE stopped, then?
If so, it might be the fan for cooling the hybrid batteries - which are in fact under the rear seat.
Just a thought.

longne

Forgive my ignorance, but what is ICE?

That is exactly what it sounds like, something hitting a fan blade!!! Perhaps a piece of trash or something is back there in the path of the blades. I will check it out tonight and report back.

By the way, how do I access that area?

Thanks!!

smassey321

There are 3 separate fans and they look to be on the back side of the assembly. Removing everything to get to them is a bit of work. On the bright side, taking the rear seat out gets you access to vacuum the trash out.

smassey321

Here is a better picture of the fans. This was taken from the drivers side. Seats have been removed and carpet was folded forward. Looks like you can access without removing the entire unit which is good news.

maseace

Probably something got sucked into one of the battery cooling blowers, or a blower is going bad.

spacecraft

Stands for Internal Combustion Engine, sorry for being unclear but it's an acronym often used with hybrid cars, to distinguish from electric motor(s).

Re. your other question, you already got some good advice.

Good luck for your troubleshooting, and let us know the result!
...you never know, it might happen also to others...

thomas1

Might also be the undercarriage plastic cover that goes under the gas tank...It can vibrate and oscillate while driving, mine has a silly bungee cord across the middle of it. I just haven't spent the time to modify whomever made this fix on the car.

spacecraft

Nah, the OP said he can hear it with the vehicle stopped.

thomas1

Ah missed that...Yup probably something in the fans...

longne

Thanks everyone for the info. I had decided to check it out this weekend, but the noise seems to have resolved itself. I can only assume it was a piece of trash on the fan blade. I may still dig into it and make sure everything is clean and clear, but for now its all good.

longne

So, the noise came back and we're going on vacation at the end of next week. I didn't want to hear that noise the whole trip. I took out the back seat and pulled up the carpet. Golf *****. There were at least 6 golf ***** rolling around back there. Not only was one stuck in the passenger side fan, but another was on in the one on the driver's side. Popped them out and I'm pretty sure fixed the problem. Apparently, the PO was a golfer. At least it gave me an opportunity to clean off the rear carpeting under the back seats.