Description
OBD-II Trouble Code Description for P0121 Volkswagen
Throttle/Pedal Position Sensor/Switch “A” Circuit Range/Performance
What does this mean?
OBD2 Code P0121 Volkswagen 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 Volkswagen
Symptoms of a P0121 Volkswagen 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 Volkswagen
A code P0121 Volkswagen 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 Volkswagen:
2013 Volkswagen e-Co-Motion Concept,2013 Volkswagen Up 4-door,2013 Volkswagen Up,2013 Volkswagen Touareg Edition X,2013 Volkswagen Scirocco GTS,2013 Volkswagen Santana,2013 Volkswagen Polo R WRC,2013 Volkswagen Polo BlueGT,2013 Volkswagen Passat Alltrack,2013 Volkswagen Lavida,2013 Volkswagen Kombi Last Edition,2013 Volkswagen Jetta Hybrid,2013 Volkswagen Golf Sportsvan Concept,2013 Volkswagen Golf Plus Life,2013 Volkswagen Golf Mk VII UK-Version,2013 Volkswagen Golf GTI Cabriolet,2013 Volkswagen Golf,2013 Volkswagen Gol 2-door,2013 Volkswagen Eco Up,2013 Volkswagen Caddy Cross,2012 Volkswagen Tiguan,2012 Volkswagen Jetta GLI,2012 Volkswagen Beetle,2011 Volkswagen eT Concept,2011 Volkswagen e-Up Concept,2011 Volkswagen XL1 Concept,2011 Volkswagen Touran,2011 Volkswagen Touareg,2011 Volkswagen Sharan,2011 Volkswagen Polo GTI,2011 Volkswagen Phaeton,2011 Volkswagen Jetta,2011 Volkswagen Eos,2011 Volkswagen CrossTouran,2011 Volkswagen CrossPolo,2011 Volkswagen CrossGolf,2011 Volkswagen Amarok,2010 Volkswagen Polo,2010 Volkswagen Golf,2009 Volkswagen Phaeton,2009 Volkswagen Golf,2009 Volkswagen Gol,2008 Volkswagen Phaeton,2008 Volkswagen Golf Variant,2008 Volkswagen Golf GTI Concept,2008 Volkswagen Golf BlueMotion,2007 Volkswagen Up Concept,2007 Volkswagen Touran,2007 Volkswagen Touareg,2007 Volkswagen Eos,2006 Volkswagen Rabbit,2006 Volkswagen Passat,2006 Volkswagen Jetta,2006 Volkswagen Eos,2006 Volkswagen CrossPolo,2005 Volkswagen Touareg,2005 Volkswagen Golf,2005 Volkswagen Fox,2004 Volkswagen RaceTouareg,2004 Volkswagen Golf,2004 Volkswagen Concept T,2004 Volkswagen Concept C,2003 Volkswagen Touran,2003 Volkswagen Passat
Note:
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