Description
OBD-II Trouble Code Description for P0121 Infiniti
Throttle/Pedal Position Sensor/Switch “A” Circuit Range/Performance
What does this mean?
OBD2 Code P0121 Infiniti 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 Infiniti
Symptoms of a P0121 Infiniti 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 Infiniti
A code P0121 Infiniti 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 Infiniti:
,2013 Infiniti M35h GT,2013 Infiniti JX,2013 Infiniti FX,2011 Infiniti QX,2011 Infiniti M35h,2011 Infiniti M,2011 Infiniti JX Concept,2011 Infiniti IPL G Coupe,2011 Infiniti EX30d,2009 Infiniti G37,2009 Infiniti FX50,2009 Infiniti FX37,2009 Infiniti FX35,2009 Infiniti Essence Concept,2009 Infiniti EX37,2008 Infiniti QX56,2008 Infiniti M45x,2008 Infiniti M45s,2008 Infiniti G37 Coupe,2008 Infiniti EX35,2007 Infiniti G35 Sedan,2007 Infiniti EX Concept,2006 Infiniti QX56,2006 Infiniti Q45,2006 Infiniti M45,2006 Infiniti M35x,2006 Infiniti M35,2006 Infiniti FX45,2005 Infiniti Q45,2005 Infiniti G35,2005 Infiniti FX45,2004 Infiniti QX56,2004 Infiniti M45 Concept,2004 Infiniti I35,2003 Infiniti QX4,2003 Infiniti Q45,2003 Infiniti M45,2003 Infiniti I35,2003 Infiniti G35,2003 Infiniti FX45,2003 Infiniti FX35
Note:
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