^^ Thanks for pointing out those videos. Looks like removing the cowl and windshield wiper assembly is indeed the way to access the three rear spark plugs, although the working room still looks to be very tight back there. I have monster-sized hands and I am not looking forward to doing this job when the time comes. Having the right socket wrench extensions and swivels seems to be crucial as well.

For anyone who has already done this job on a 3rd Gen RX350 via the cowl / wiper assembly removal method, please post your tips and tricks here. Much obliged.

 

Couple key tools: 5mm hex to remove the upper intake. If you look at it, you will want to have a long version of the hex to make it easier. The other is mid/long 10mm socket. It will make it easier. Other than that you just use 12 and 14 in a couple places. Removing wiper and related stuff is actually pretty easy but do ensure you know where the wiper set before removal, otherwise, it might ended up being set too high or too low.

 

Another detailer blew the fuses
picked up car and pull out and discover I'm in limp mode.
Took it to mechanic I trust around the corner. They tried to reset the system didn't work so said they would run the diagnostic tool but they were closing so couldn't do it then.
I look up the issue online and find the same scenario multiple times.
Mechanic was speculating all the possible causes. Got them to check fuses next day, 3 blown with burn marks. Replaced them and problem resolved .

 

Do you know which fuses were blown?

 

When I tried to start my car (kids kept doors open for a while on an 3 years old A/M AAA battery), first I got check AWD system, TRAC OFF messages and car wouldn't start.

Called AAA Roadside assistance and they cranked up the battery. Car started but Check AWD System, TRAC OFF, and Check Engine light wouldn't go away. I started driving and car has no power or whatsoever, it just rolled according to the road conditions (rolled down on a slope, crawled on high hills, I needed to get home as it's already 12:00 midnight and I was only 5 miles away).

Is it because of the week battery or do I have a major problem that I need to spend a lot to get my car on road again?

 

Please don't let your imagination run wild.

Did the AAA service determine that you need a new battery? Did the tech connect an OBDII diagnostic tool? Have you had a chance to charge up your depleted battery after the boost?

You can visit auto parts store and they can test your battery and charging system as well as give you OBDII test results for free. These readers are fairly cheap and you can read and clear error codes..

A health battery is a must, before pursuing any error codes.

Salim

 

AAA did say I needed a new battery. I'll sure have someone run the diagnostics today. Thanks for your response

 

I have the codes checked now.
P2118
P0717

 

Just get a new battery and all those codes will go away.
The AAA driver already advised that that is what you need. It died on you once. Keep driving on a weak battery and you will kill your alternator as it works too hard trying to charge the worn out battery. As Salim said, random codes such as those you posted are another sign of a dying battery.
Do not waste time or money on further diagnostics unless they persist for a couple of weeks after the new battery is installed. Sometimes it takes a while for these random codes to self clear.

 

****UPDATE******
So, I finally have my car back on road!!!.

After the freelance mechanic changed the throttle body and couldn't program it I took the car to dealer. Dealer found a couple of blown fuses. They changed the fuses, recalibrated the computer for a flat hourly fee. The Service manager said they checked everything and no problem with the car battery.

 

Have a 2013 Lexus RX350 - 108,000 mn - AWD warning light been on and off for months
Replaced the battery after it went dead - thought that would work.. Nope on the light came again
Had a TPMS issue as well and got those replaced for 50 dollars each at Costco - a good deal
Resolved - Nope on the light came again..
Took it to the Lexus dealer this week and they did the full diagnostic check and could not identify the issue
The warning only comes on after you have been driving a while
They said car was in good shape and was driving fine and just ignore it for now
Did not charge me for the check..
Only issue with car was excessive rust underneath
Guess no other option - not worth spending a lot of money to find the problem

 

How is the treadwear on all four of your tires? If they are not all approximately the same, that could be the cause. Many AWD systems do not like having one or more tires having more treadwear than the others.

 

Check that the gas cap is tight and has a proper seal.

Also try disconnecting the battery cable for a few minutes.

Try a bottle of Techron Fuel System Cleaner (20 ounce size) in the gas tank to help clean the fuel system. Pour it in when you fill up with gas.

 

Got two new tires in December
However this problem was before i got new tires - new batteries - new TPMS...

Amazed Lexus said car is good and we can not find problem

 

I find it hard to believe they actually checked properly if they could not find out the cause for the light. That should be a stored "history" code in the ECU which should easily be able to be scanned, especially with a higher end scan tool.