Description
OBD-II Trouble Code Description for P0120 Volkswagen
Throttle/Pedal Position Sensor/Switch “A” Circuit
What does this mean?
OBD2 Code P0120 Volkswagen definition:
The TPS (Throttle Position Sensor) is a potentiometer that is mounted to the throttle body. It detects the throttle blade angle. As the throttle blade moves, the TPS sends a signal to the PCM (Powertrain Control Module). Usually a three wire sensor: A 5 volt reference from the PCM to the TPS, a ground from the PCM to the TPS, and a signal return from the TPS to the PCM.
The TPS sends the throttle position information back to the PCM on this signal wire. When the throttle is closed the signal is near .45 volts. At WOT (Wide Open Throttle) the TPS signal voltage will approach a full 5 volts. When the PCM sees a voltage that is outside of normal operating range, P0120 Volkswagen will set.
NOTE: The PCM knows that any large change in throttle position means a cooresponding change in manifold pressure (MAP). On some models the PCM will monitor MAP and TPS operation for comparison. Meaning that if the PCM sees a large percentage change in throttle position, it expects to see a cooresponding change in manifold pressure and vice versa. If it doesn’t see this comparitive change, P0120 Volkswagen may set. This doesn’t apply to all models.
Symptoms
Possible sumptoms of OBD code P0120 Volkswagen
Potential symptoms include:
MIL (Malfunction Indicator Lamp) illumination
Misfiring at idle or at highway speed
Poor idle quality
Possibly won’t idle
Possibly starts and stalls
Causes
Possible causes of OBD code P0120 Volkswagen
Potential causes of the P0120 Volkswagen code include:
Sticking throttle return spring
MAP or TPS connector corrosion
Misrouted harness causing chafing
Bad TPS
Bad PCM
Possible Solutions
If you have access to a scan tool, with KOEO (Key on engine off) observe the TPS voltage. With throttle closed, voltage should be about .45 volts. It should gradually sweep upwards to approximately 4.5 to 5 volts as you depress the throttle. Sometimes only a scope can capture an intermittent glitch in the TPS signal voltage. If you notice a glitch in the TPS sweep voltage, replace the TPS.
NOTE: Some TPS sensors require fine adjustment. If you aren’t comfortable with using a DVOM (Digital Volt Ohm meter) to adjust the new TPS, then it’s best to take the vehicle to a shop. If the voltage is not .45 volts (+or- .3 volts or so) with the throttle closed or if the reading is “stuck” then unplug the TPS connector. With KOEO check for 5 volts reference voltage present at the connector and a good ground. You can check the signal circuit for continuity by jumping a fused wire between the ground circuit of the TPS connector and the signal circuit. If the TPS reading on the scan tool now reads zero, then replace the TPS. However if that doesn’t change the reading to zero, then check for an open or a short on the signal wire and if none is found, suspect a bad PCM. If manipulating the TPS wiring harness causes any change in idle, then suspect bad TPS.
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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