Help! Check Engine P2121 Code
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Driver School Candidate
Joined: May 2016
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From: GA
Help! Check Engine P2121 Code
Need some help guys. I have a 2004 RX330 around 110k miles. My wife was driving home the other day and check engine light, VSC and Trac Off lights all came on and throttle power is very low. Can barely get RPM to 2000 or 3000 rpms. I googled the code (P2121) and it said to replace Accelerator Pedal Sensor (Gas pedal). I removed cleaned the throttle body and installed new pedal and still have lights on and won't get up to 3000 rpms. Any suggestions? How do I reset the lights? I have had both battery cables off for an hour and it won't clear the memory. Radio still has presets, but windows and memory seats have lost memory. Please help on what I should do next
Thanks
Thanks
Last edited by Ahsalloum; May 11, 2016 at 06:18 PM. Reason: Misspelling
Pit Crew
Joined: Feb 2016
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From: CA
How long was the battery unhooked? 15 minutes always works for me. I believe by depressing the brake pedal it completely discharges any electricity left in the system. Also, you can get a code reader for $20 and erase the code yourself.
You replaced the accelerator pedal sensor with an OEM part?
There are code readers for ABS and SRS:
Also, here's a link for the TSBs for your model year, even though you are out of warranty, it's good info:
https://www.automd.com/tsb/lexus_m/r...2004_y/?page=3
You replaced the accelerator pedal sensor with an OEM part?
There are code readers for ABS and SRS:
Also, here's a link for the TSBs for your model year, even though you are out of warranty, it's good info:
https://www.automd.com/tsb/lexus_m/r...2004_y/?page=3
Thread Starter
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From: GA
Yes, I left both cables disconnected for at least 45 mins and still didn't clear everything. Should I just be disconnecting the ground cable or both cables. I have heard both ways.
Do you think if I am able to clear the check engine light, the car will start to drive normal? At least until it reads an error again.
Yes, I replaced the pedal I bought from Lexus for $67. I cleaned the throttlend body the best I could and I unplugged the MAF sensor while car was on and the car cut off, so I am assuming the MAF is good.
Do you think if I am able to clear the check engine light, the car will start to drive normal? At least until it reads an error again.
Yes, I replaced the pedal I bought from Lexus for $67. I cleaned the throttlend body the best I could and I unplugged the MAF sensor while car was on and the car cut off, so I am assuming the MAF is good.
Thread Starter
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From: GA
Update; I left both battery cables disconnected last night and the check engine, VSC and Trac Off lights are still on. Can't seem to get them to clear. Everything finally seems to lose memory, so that should have done it, but no dice.
With putting in a new accelerator pedal sensor and cleaning out the throttle body, what else should I do with this error message?
I have also checked the gas cap numerous times.
With putting in a new accelerator pedal sensor and cleaning out the throttle body, what else should I do with this error message?
I have also checked the gas cap numerous times.
Pit Crew
Joined: Feb 2016
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From: CA
You can either look up how to reset the VSC and Trac, or buy a scan tool and turn it off yourself.
I'll just leave this here for you:
https://www.clublexus.com/forums/rx-...rol-light.html
I'll just leave this here for you:
https://www.clublexus.com/forums/rx-...rol-light.html
Thread Starter
Driver School Candidate
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From: GA
Thanks Numbafree.
Does anyone know what else I need to do to get my car working? Changed the accelerator pedal sensor as the error suggests and still can't rev car past 2000 rpms
Does anyone know what else I need to do to get my car working? Changed the accelerator pedal sensor as the error suggests and still can't rev car past 2000 rpms
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Pit Crew
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From: CA
Not sure if you did a search:
http://my.is/forums/f87/is300-code-p...d-help-447301/
http://cars-safety.com/lexus/es300/e...ne-cooling.htm
https://www.clublexus.com/forums/per...p-mode-23.html
post #336. might be your ECU. did you check the current CEL and is it still P2121? If you have a code reader, can you check pending codes? I wonder if it's throwing other codes than just the P2121.
http://my.is/forums/f87/is300-code-p...d-help-447301/
http://cars-safety.com/lexus/es300/e...ne-cooling.htm
https://www.clublexus.com/forums/per...p-mode-23.html
post #336. might be your ECU. did you check the current CEL and is it still P2121? If you have a code reader, can you check pending codes? I wonder if it's throwing other codes than just the P2121.
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From: GA
I am now getting 2 more errors (P0123 and P2135). I have cleaned the throttle body as best as I could and changed the Accelerator Pedal Sensor (gas pedal) and still did not help.
Any idea what could be wrong?
I really don't want to take it to a shop because I will have to tow it. It won't go past 1500 rpms and won't go faster than 10 mphs. Really can use the help guys
Any idea what could be wrong?
I really don't want to take it to a shop because I will have to tow it. It won't go past 1500 rpms and won't go faster than 10 mphs. Really can use the help guys
Pit Crew
Joined: Feb 2016
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From: CA
AAA is $55 for a year, and a 5 mile tow, $100 for the plus membership and you get 100 mile towing distance, no affiliation.
I don't think anyone else is responding because:
1) they would just be looking up the code for you on the internet.
2) you have a unique issue.
P2135 is throttle position sensor (TPS)
P0123 is high output for TPS. which means the ground wire is loose or disconnected, or it's a bad sensor.
Another possibility listed for both the P2121 and the P0123 is you might have a bad ecu.
http://www.obd-codes.com/p2135
http://www.obd-codes.com/p2135
I would invest in an OEM service manual, before throwing parts at this. or punt to a mechanic.
I don't think anyone else is responding because:
1) they would just be looking up the code for you on the internet.
2) you have a unique issue.
P2135 is throttle position sensor (TPS)
P0123 is high output for TPS. which means the ground wire is loose or disconnected, or it's a bad sensor.
Another possibility listed for both the P2121 and the P0123 is you might have a bad ecu.
http://www.obd-codes.com/p2135
http://www.obd-codes.com/p2135
I would invest in an OEM service manual, before throwing parts at this. or punt to a mechanic.
Driver School Candidate
Joined: Apr 2017
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From: Ohio
My car has been acting the same way it's a gs300. Some day are better than others with it, like today. Today it wAs running completely fine , but yesterday horrible. My car reads code P2121 circuit "D". I was told to replace the TPS. Which I did but nothing changed. My uncle did it and we didn't realize you had to calibrate it to a certain thing. Any idea how to replace this right ? The car still drives, like I said some days better than others. When it is acting up it will just take forever to accelerate and the RPM goes up pretty high but my car feels like it's not going very far. If I turn my car off for a min and then restart it , it starts acting fine till the next time it wants to start acting up. When I start my car to warm it up the RPM is always at around 1200-1500 but slowly moves now to normal once the car is heated. Is this normal? After I replaced the TPS, I was told to replace the APPS. This was supposed to fix the problem... But still now luck. Any clue what's going on ?
Driver School Candidate
Joined: Apr 2017
Posts: 8
Likes: 0
From: Ohio
My car has been acting the same way it's a gs300. Some day are better than others with it, like today. Today it wAs running completely fine , but yesterday horrible. My car reads code P2121 circuit "D". I was told to replace the TPS. Which I did but nothing changed. My uncle did it and we didn't realize you had to calibrate it to a certain thing. Any idea how to replace this right ? The car still drives, like I said some days better than others. When it is acting up it will just take forever to accelerate and the RPM goes up pretty high but my car feels like it's not going very far. If I turn my car off for a min and then restart it , it starts acting fine till the next time it wants to start acting up. When I start my car to warm it up the RPM is always at around 1200-1500 but slowly moves now to normal once the car is heated. Is this normal? After I replaced the TPS, I was told to replace the APPS. This was supposed to fix the problem... But still now luck. Any clue what's going on ?
Lead Lap
Joined: Oct 2016
Posts: 454
Likes: 73
From: California
My car has been acting the same way it's a gs300. Some day are better than others with it, like today. Today it wAs running completely fine , but yesterday horrible. My car reads code P2121 circuit "D". I was told to replace the TPS. Which I did but nothing changed. My uncle did it and we didn't realize you had to calibrate it to a certain thing. Any idea how to replace this right ? The car still drives, like I said some days better than others. When it is acting up it will just take forever to accelerate and the RPM goes up pretty high but my car feels like it's not going very far. If I turn my car off for a min and then restart it , it starts acting fine till the next time it wants to start acting up. When I start my car to warm it up the RPM is always at around 1200-1500 but slowly moves now to normal once the car is heated. Is this normal? After I replaced the TPS, I was told to replace the APPS. This was supposed to fix the problem... But still now luck. Any clue what's going on ?
Driver School Candidate
Joined: Apr 2017
Posts: 8
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From: Ohio
Try this: unplug your negative battery cable for at least 30 seconds. Reinstall it, start car and let it idle for five minutes, then go drive it. Use every gear, including reverse. See if that allows your ecu to recalibrate system. You'll need to reinitialise power functions such as windows. Consult manual for this, it's easy.
