tungsten24

First post here and I hope to get some good advice here. I have a 2010 RX350 with 115K miles. Bought the car with 33K miles and have been running like a champ until recently when suddenly the AFS, ABS and AWD check messages comes and goes on the meter randomly.

Before I post here, I thought I try to figure out what could be the cause but after a month, I could not
come to an conclusion so I am here for help.

Here are some thing I have noticed over a month.

1. When the lights are off and driving, right before all the lights decide to come back on, I feel the brake "slipping" when coming to a complete stop. Shortly after is whe the lights generally come on. Then after some random time, the light will go away again.

2. Just yesterday, justbfor a brief moment, a new message appeared and never seen again. It was "AWD overheat".

3. Rotors and pads were replaced last June and are brand new. OEM pads and rotors are decent aftermarket but Equivalent to OEM product.

4. I know I have a bad rear driver bearing which I plan to replace in next month or so.

Based on these I have an assumption that it maybe sensor related but I am not positive and can't figure out where to look from.

I can answer any questions. I just want to see if it is something I can fix myself or need to take it to a dealer. Dealer here wants $175 just to look at it.

One last nite, my car did suddenly die 2 in the past 2 months although I had put a new battery in 2 years ago. Took it to Advance Auto and the said I am at 12.6V and 460 CCA. Not the best but should be okay.

Thanks for reading and and I hope that I get some help here. Thank you very much!

tungsten24

I am in desperate need of advice...... thank you.

Clutchless

I think this is too complicated to diagnose over the internet. I will ask if you ever had the brake fluid flushed because you had a warning of ABS overheat. That (expensive) component may be failing and a cause could be old, water logged, contaminated brake fluid. You could try to have Advance Auto pull any stored codes, (if there are any). I think that is free.

However, I think you need to take it to the dealer or a very good independent shop for proper diagnosis. You cannot just throw parts at something like this without knowing what is actually the cause of the warning lights. You could try this site to maybe locate a great independent shop that would be cheaper than the dealer
http://www.cartalk.com/mechanics-files

I found this thread that may or may not be related https://www.clublexus.com/forums/rx-...and-p0430.html

iginoc

You have written about a bad bearing... it is possible that the friction due to the bad bearing increases the rolling resistence of the interested whell, which may lead to an overload of the ABS ECU, as well as to overheat the rear motor generator. If I were you, I would have the bearing changed asap.

tungsten24

Thank you for your advice. I have a feeling it is sensor related because the lights go off and on.

Also, since I feel ABS kicking in, maybe speed sensor? It is too complicated but I am just afraid the dealer repping me off.

So ABS sensor or speed sensor maybe?

Clutchless

First fix the bearing.

NateJG

Do you trust the competence of the brake reline technician with respect to ensuring that the abs sensors were not compromised?

Your brake release symptom could be caused by an errant sensor - especially just prior to coming to a stop - which is where the signal strength would normally be near its weakest.

The AWD overheat indicator is a head-scratcher.

p.s.: if the bearing issue causes an alignment or runout issue with a related sensor, you could find the two (ABS & Bearing) to be closely related.

Johnhav430

Not sure how helpful this will be, but in the BMW world there is something called the trifecta, which is a similar warning where there is no ABS, no stability, cruise doesn't work anymore, etc. The cause is usually 2 things--either the failure of the ABS pump, or a wheel speed sensor. The fault codes indicate what the issue is. The latter is not very expensive, the former is $4,200 at the dealership. Because it's a relatively common issue, there is lots of info on the BMW forums, and a user can actually repair the ABS pump for about $250. Not sure if there is similar info or fixes for Lexus... my hunch is the repair service is not available for Lexus as it's not as common of a failure.

tungsten24

Sorry everyone for my delayed response.

I will be working on the car this weekend to identify the problem with the car.
I do see that the wheel bearing could be the culprit based on everyone's inputs.

I typically go OEM for most parts, but dealer costs are ridiculous. I would like to
know if any of you recommend any online parts store that you can refer me to.

As you can tell, I am probably not mechanically intelligent like most of you and
don't have the knowledge and experience like most of you do. So any advice is
appreciated.

My family depend on this car, so I want to get this fixed. Taking it to a dealer
to diagnose the problem is the best, but they just want so much. Not that I am
being cheap, but I can't be spending thousands when I have 3 kids to take care of.

Anyway, any additional advice is appreciated.

By the way, does anyone know if 2010 Lexus bearing is pressed on or bolt on?
I assume it is bolt on type.....

Thank you!

Clutchless

I like RockAuto. However, this is not something to do if you do not work on cars. You probably do not have the appropriate tools. Any local gas station, independent shop can replace a bad rear wheel bearing. Here is a link to http://www.rockauto.com/en/catalog/lexus,2010,rx350,3.5l+v6,1444184,brake+&+wheel+hub,wheel+bearing+&+hub+assembly,1636

It looks like a bolt on assembly per the photos at Rockauto

tungsten24

Mr.Clutchless,

Thank you so much for the quick response.

I will go check out the site right after posting this reply.

I have worked on cars with some help and I do have some tools, but
maybe not the exact tools needed for this job.

I have a friend that I work with that works on cars and I know
I can trust him, so I will work on it with him.

I will keep my status updated here. Thank you!

tungsten24

Sorry for another post.

I think I need to get the AWD rear hub assembly.

I am planning to get it from standard replacement list, but
the difference is just the brand and quality?

Thank you!

Clutchless

I would get the Timken or SKF over the Moog.

tungsten24

Thanks you so much for your help.

I am going to order one today and replace it as soon as it arrives.

My buddy and I did a visual inspection of the wheel speed sensor.
From what we can tell, no issues with the wheel speed sensor.

So now, I really think the bearing is causing this issue. I will fix what
is broken first and then proceed with other parts.

I think bad bearing can cause bad reading from the wheel speed sensor.

I will keep you posted. Thank you!

salimshah

If your code reader can pin point to which sensor is bad, you can swap the sensor from right side to the left and see if the problem moves.
If you decide to change the bearing and if you have enough milage [swag 50K miles], consider changing the other bearing pair too. Change cost adds up real quick.

Salim