Notices
SC - 1st Gen (1992-2000)

weird check engine light and trac light problem.

Thread Tools
 
Search this Thread
 
Old Nov 4, 2013 | 09:26 PM
  #1  
CheVelleSS's Avatar
CheVelleSS
Thread Starter
Rookie
iTrader: (1)
 
Joined: Jan 2011
Posts: 50
Likes: 0
From: Tulsa Oklahoma
Default weird check engine light and trac light problem.

One day my check engine light and trac off light came on. Its never came on before on me. Well I continued driving it and the light went off. I didnt see if for a couple of days but it came back on and off every once in a while. Well It now comes on every time I start the car and slowly dims out and the trac off light just pops off when it starts to dim. Well I checked codes. 21 28 and 41 came up. SO I figured it was the TPS causing this weird light problem. Cause the light will vary with brightness with the throttle but only while its in gear, not in park or neutral. So bought new toyota tps, installed adjusted. All is good but Check engine light is still on. Only codes left are 21 and 28. I do not understand why the check eng light would vary with throttle with Oxygen sensor codes only.
Guess I will buy new upstream o2s and hope the light and code problem goes away. But for some reason im doubting it will.
Reply
Old Nov 5, 2013 | 12:28 PM
  #2  
Vrank's Avatar
Vrank
Lexus Test Driver
iTrader: (4)
 
Joined: Feb 2011
Posts: 969
Likes: 2
From: TX
Default

There's no load on the engine free revving or at idle, but there is when driving. Possible you're having charging issues too. Only reason I can think of that a light gets brighter with throttle.

The way the check engine light works is that power is supplied to the light, and fed into the ecu. When there's a problem, the ecu provides a ground. So yeah, unless your ecu is going bad which is quite possible too, I'd also go through things that'll effect charging along with figuring out the o2 stuff.
Reply
Old Nov 5, 2013 | 12:39 PM
  #3  
Ali SC3's Avatar
Ali SC3
Lexus Champion
CL Folding 100,000
15 Year Member
Liked
Community Favorite
iTrader: (10)
 
Joined: Oct 2007
Posts: 10,808
Likes: 472
From: CO
Default

ecu sounds suspect, I would open it up and take a look.
Reply
Old Nov 5, 2013 | 06:28 PM
  #4  
CheVelleSS's Avatar
CheVelleSS
Thread Starter
Rookie
iTrader: (1)
 
Joined: Jan 2011
Posts: 50
Likes: 0
From: Tulsa Oklahoma
Default

well I ordered 2 new upstream denso oxygen sensors. I hope that fixes it. If not I will take a look at the ecu and figure out if theres any broken solder joints and any obvious damage. Any idea where to look inside the ecu? I know I had a hard time retrieving codes.
Reply
Old Nov 5, 2013 | 07:26 PM
  #5  
usoff89's Avatar
usoff89
Lexus Test Driver
iTrader: (2)
 
Joined: Jun 2012
Posts: 1,145
Likes: 4
From: florida
Default

You would be looking for leaking capacitors and any other obvious damage.
Reply
Old Nov 6, 2013 | 05:16 PM
  #6  
hoosier58's Avatar
hoosier58
Pole Position
 
Joined: Dec 2011
Posts: 243
Likes: 1
From: co
Default

I can't remember where I read it (maybe the owner's manual?), but I think the CE and Track Off together indicates a limp mode, and needs to be addressed quickly.
Reply
Old Nov 6, 2013 | 05:39 PM
  #7  
Vrank's Avatar
Vrank
Lexus Test Driver
iTrader: (4)
 
Joined: Feb 2011
Posts: 969
Likes: 2
From: TX
Default

It takes 10 minutes and zero dollars to look at an ecu. How are you gonna feel if the primary o2s don't do anything? To play devils advocate, the fact that replacing the tps eliminated the tps code is a good sign. What do you mean you had trouble retrieving codes?
Reply
Old Dec 14, 2013 | 03:30 PM
  #8  
CheVelleSS's Avatar
CheVelleSS
Thread Starter
Rookie
iTrader: (1)
 
Joined: Jan 2011
Posts: 50
Likes: 0
From: Tulsa Oklahoma
Default

Well your right it ended up being the ECU. I pulled it apart and found 6 leaking capacitors. 2 Of those 6 destroyed other circuits by corroding them. after replacing them and fixing the bad circuits the engine light and trac light have not came back on. Thanks for the help.
Reply
ClubLexus Stories

Celebrating Lexus & Toyota from Around the Globe

story-0

Toyota and Lexus Join Mille Miglia For The First Time

 Verdad Gallardo
story-1

Lexus NX 350h: A Fuel-Sipping Secret Hot Hatch???

 Michael S. Palmer
story-2

5 Best & 5 Worst Lexus Daily Drivers

 Joe Kucinski
story-3

Top 5 Hottest Lexus & Toyotas in 2026 (Hardest To Buy)

 Brett Foote
story-4

2026 Lexus IS 350 F Sport Review: The Last of Its Kind Still Rocks

 Michael S. Palmer
story-5

Top 10 Most Confusing Things Lexus Has Ever Done!

 Joe Kucinski
story-6

2026 Lexus ES Review: Lexus Re-Embraces Founding Principles

 Michael S. Palmer
story-7

10 Lexus Bargains That are Cheaper Than a New Toyota RAV4

 Joe Kucinski
story-8

8 Weirdest Things Lexus Has Ever Built

 Verdad Gallardo
story-9

10 Lexus Designs That Have Aged Like Fine Wine

 Verdad Gallardo
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mechanChic
SC - 1st Gen (1992-2000)
8
Oct 17, 2012 10:32 PM
lexsc3
SC - 1st Gen (1992-2000)
14
Apr 5, 2011 06:24 AM
chriswins
LS - 1st and 2nd Gen (1990-2000)
2
Aug 20, 2009 05:27 PM
Jasoneo5
LS - 1st and 2nd Gen (1990-2000)
4
Mar 6, 2004 02:55 PM
lexsc3
SC - 1st Gen (1992-2000)
4
Jan 3, 2003 01:59 PM




All times are GMT -7. The time now is 07:24 PM.

story-0
Toyota and Lexus Join Mille Miglia For The First Time

Slideshow: A five-car lineup spanning more than five decades of Toyota performance and engineering will tackle one of Italy's most celebrated automotive routes.

By Verdad Gallardo | 2026-06-15 16:53:16


VIEW MORE
story-1
Lexus NX 350h: A Fuel-Sipping Secret Hot Hatch???

Slideshow: a quick review of the 2026 Lexus NX 350h F Sport Handling

By Michael S. Palmer | 2026-06-15 15:25:34


VIEW MORE
story-2
5 Best & 5 Worst Lexus Daily Drivers

Slideshow: The 5 best and 5 worst Lexus daily drivers

By Joe Kucinski | 2026-06-15 11:14:58


VIEW MORE
story-3
Top 5 Hottest Lexus & Toyotas in 2026 (Hardest To Buy)

These five Lexus and Toyota models are the most sought-after on the market right now.

By Brett Foote | 2026-06-15 10:47:52


VIEW MORE
story-4
2026 Lexus IS 350 F Sport Review: The Last of Its Kind Still Rocks

Slideshow: the 2026 IS 350 isn't all that new, and that's why we love it!

By Michael S. Palmer | 2026-06-04 14:35:23


VIEW MORE
story-5
Top 10 Most Confusing Things Lexus Has Ever Done!

Slideshow: 10 most confusing things Lexus has ever done.

By Joe Kucinski | 2026-06-04 09:40:55


VIEW MORE
story-6
2026 Lexus ES Review: Lexus Re-Embraces Founding Principles

Slideshow: Our First-Drive Review of the 2026 Lexus ES!

By Michael S. Palmer | 2026-05-29 20:30:16


VIEW MORE
story-7
10 Lexus Bargains That are Cheaper Than a New Toyota RAV4

Slideshow: 10 Lexus bargain that are cheaper than a new Toyota.

By Joe Kucinski | 2026-05-20 10:28:20


VIEW MORE
story-8
8 Weirdest Things Lexus Has Ever Built

Slideshow: From hoverboards to luxury yachts, these are the strangest projects Lexus has ever attached its badge to.

By Verdad Gallardo | 2026-05-16 11:34:36


VIEW MORE
story-9
10 Lexus Designs That Have Aged Like Fine Wine

Slideshow: Some luxury cars chase trends, but these Lexus models look better now than they did when they first rolled into showrooms.

By Verdad Gallardo | 2026-05-06 17:58:29


VIEW MORE