johncdub

My warning lights came on as I was getting to work this morning. After googling my problem and being led to this forum, I just joined up. The responses I've read seem spot on and I will hook up my OBD tool and hopefully get the O2 sensor code. If replacing it increases mpg all the better. My model is a 2001 RX300 with 180,000 miles. It is in exceptionally good condition and I'm relying on it to get me through the winters here in NE Ohio. I'll update on my progress. Thanks.

JAB

Where in NE Ohio? I'm originally from Chagrin Falls.

johncdub

A close neighbor. Solon. Snow is starting to come. Miss it?

Kevvo1

I have similar issues on 01 Rx300

OBDII codes: P1135, P1155, C1201
2 Denso A/F sensors on way. I hope it fixes the C1201 also.

Found out I have burnt CEL bulb for sure, and I think VSC and Trac Off as well :'(
Can anyone confirm that all three lights are supposed to illuminate with C1201?
Also confirm that those three are supposed to be on in ACC mode before startup?

salimshah

Best source of what bulbs light up during self test is the owners manual. Members can have their bulb burnt too.

Salim

Kevvo1

So I replaced the 2 A/F sensors with Denso part# 234-9009 (MUST be these OEM sensors).
Cleared data on OBD2 reader; P1135, P1155, and C1201 codes are now gone!

Regarding the bulbs, my owners manual still hasn't come in the mail yet.
I took apart my instrument panel to find out some idiot removed the VSC, TRAC OFF, and CEL lights!!
I replaced the missing bulbs and YES on the 01 Rx300 they are supposed to illuminate while in ACC mode (VSC & TRAC OFF only momentary).

P.s. I cannot say replacing the 2 A/F sensors fixed the 3 lights, as I found out the bulbs were missing AFTER changing the sensors.

SBailey

I have had 4 of my coil packs go bad. Now again! I guess all six will be new. Similar description as #40 above.

gjonesgrad

Great thread. My VSC, Trac Off, Check Engine lights were all going off. I tightened gas cap and re-seated all the fuses (no picture for specific fuse posted). Also checked the hoses in the back of the air filter. After I did all of that, no more indicator lights. It was a great feeling. Thanks again all.

01rxwhite

My 2001 RX with 313300 miles has recently had the CEL, VSC, and Trac Off lights coming on intermittently. When I start the engine, the CEL light immediately comes on, then after about 10 seconds or so, the others come on. I have read this thread and these codes seem to be most associated with AF sensors. Yesterday while the code lights were off, it showed P0128, regarding the thermostat. Today after the lights came on again, it showed the C1201 code, 'engine communication circuit'? I haven't found where these two codes associated together in previous posts. After researching posts on each, I'm leaning on the thermostat replacement (P0128) to see if that takes care of the problem and could be causing the C1201 code. Are there any suggestions or other areas I should be looking at? I was thinking if the thermostat didn't do it, I could next replace AF sensors maybe. Suggestion on where and what to do first?

frank12933

great informations guy, thanks

jlvandat

Just a quick note to those with ~2002 RX300 or any Lexus with similar air filter/intake system: As mentioned in other posts, there is a rubber vacuum line that comes from the air filter housing and attaches to a vertical metal tube just behind and below the filter housing assembly. That line easily comes off when you lift the cover on the air filter housing to, for example, change the air filter. If it comes off, you will get the CEL, VSC and Trac Off warning lights. Re-attaching the hose is a pain in the butt, but can be done with effort and small hands. I added a 4 inch rubber hose extension to mine so it won't come off every time I remove the air filter housing cover. Once you have secured the vacuum line, the warning lights will remain on and will not clear until you detach battery cable for a minute and then reattach.

YTW9988

I have a 2003 RX300 which I bought in December 2002. It has a bit over 200,000 miles on it. Yesterday afternoon, all of a sudden, the VCS, CEL, and the Trac warning lights all illuminated and stayed on. I drove about 25 miles to the dealership in Seaside, California. They checked my vehicle in and gave me a loaner RX450h which is a very wonderful car. I asked the customer service that I would like to get the codes of whatever that malfunctioned. I went to pick it up this afternoon. The paper says: P0446 EVAP MALFUNCTION. MONITORS SHOW EVAP GROSS LEAK. PRESSURE TESTED FUEL SYSTEM AND FOUND NO LEAKS. CLEARED CODES. VEHICLE BACK TO NORMAL OPERATION.
Best of all, the dealership DID NOT charge me and washed my vehicle sparkling clean. I am very grateful to them.
In 2007 and, again, at 4 PM on December 31, 2013, in a grocery store parking lot, the engine would not start. The second time this happened, I called the AAA and the tow truck drive depressed the acceleration pedal all the way down to get the engine started. He said to me" "when the automatic does not work, you have to do it manually,", meaning that there was an idle problem. I was able to drive 80+ miles to return home on New Year's Eve. Both times, the Idle Valve Assembly had to replaced due to soot buildup inside of it. An $800 job.

YTW9988

Sorry, my RX300 was purchased in December 2002, not 2012.

Lexmus

Next time try cleaning the idle air control valve and save the $800
https://www.clublexus.com/forums/rx-...-write-up.html

Prayford65

I drive a RX330 I realize its a bigger engine compared to the 1st generation. What does it mean with both of these light come on the dash board?