Description
OBD-II Trouble Code Description for P0121 Toyota
Throttle/Pedal Position Sensor/Switch “A” Circuit Range/Performance
What does this mean?
OBD2 Code P0121 Toyota definition:
The Throttle position sensor is a potentiometer that measures the amount of throttle opening. As the throttle is opened, the reading (measured in volts) goes up. The powertrain control module (PCM) supplies a 5 Volt reference signal to the throttle position sensor (TPS) and usually a ground also. A general measurement is: at idle = .5 Volts; full throttle = 4.5 Volts. If the PCM detects that the throttle angle is greater or less than it should be for a specific RPM, it will set this code.
Symptoms
Possible sumptoms of OBD code P0121 Toyota
Symptoms of a P0121 Toyota trouble code could include: Malfunction Indicator Lamp (MIL) illumination (Check Engine Light or Service Engine Soon light) Intermittent stumble on acceleration or deceleration Blows black smoke on acceleration No start
Causes
Possible causes of OBD code P0121 Toyota
A code P0121 Toyota may mean that one or more of the following has happened: TPS has intermittent open or short internally Harness is rubbing and causing an open or short in the wiring Bad connection at the TPS Bad PCM (less likely) Water or corrosion in connector or sensor
Possible Solutions
1. If you have access to a scan tool, see what the idle and WOT (wide open throttle) readings are for the TPS. Check if they’re close to the specifications mentioned above. If not, then replace the TPS and re-check. 2. Check for an intermittent open or short in the TPS signal. To do that, you can’t use a scan tool. You’ll need an oscilliscope. The reason is because scan tools take samplings of many different readings over just one or two data lines and can miss an intermittent drop out. Hook up your oscilliscope and watch the signal. It should sweep up and down smoothly with no drop outs or spikes. 3. If no problems were noticed, perform a wiggle test. Do this by wiggling the connector and harness while watching the pattern. Does it drop out? If so, replace TPS and re-check. 4. If you have no TPS signal, check for 5 Volt reference at the connector. If it’s present, check the ground circuit for open or shorts. 5. Make sure the signal circuit isn’t 12V. It should never have battery voltage. If it does, trace circuit for short to voltage and repair. 6. Look for any water in the connector and replace TPS as necessary.
The OBD2 Code Information Be Applicable For Toyota:
2013 Toyota Auris,2012 Toyota Yaris,2012 Toyota Verso-S,2012 Toyota Tacoma,2012 Toyota Prius V,2012 Toyota Prius C,2012 Toyota Prius,2012 Toyota Hilux,2012 Toyota Camry,2012 Toyota Avensis,2012 Toyota Aurion,2012 Toyota 86 GTS,2011 Toyota Tacoma,2011 Toyota Sienna,2011 Toyota Sequoia,2011 Toyota RAV4,2011 Toyota Matrix,2011 Toyota Highlander,2011 Toyota Corolla,2011 Toyota Avalon,2011 Toyota Auris HSD,2010 Toyota iQ3,2010 Toyota Yaris,2010 Toyota Verso,2010 Toyota Tundra,2010 Toyota Prius,2010 Toyota Land Cruiser,2010 Toyota Corolla,2010 Toyota Camry,2010 Toyota Auris,2010 Toyota 4Runner,2009 Toyota iQ,2009 Toyota Yaris,2009 Toyota Venza,2009 Toyota RAV4,2009 Toyota Matrix,2009 Toyota Hilux,2009 Toyota Aygo,2009 Toyota Avensis,2009 Toyota Aurion,2009 Toyota 4Runner,2008 Toyota Sequoia,2007 Toyota Tundra,2007 Toyota Avensis,2006 Toyota RAV4,2006 Toyota Aurion,2005 Toyota Corolla Sedan,2004 Toyota Prius,2004 Toyota Corolla,2003 Toyota RAV4,2003 Toyota Land Cruiser,2003 Toyota Celica
Note:
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