Description
OBD-II Trouble Code Description for P0121 Jeep
Throttle/Pedal Position Sensor/Switch “A” Circuit Range/Performance
What does this mean?
OBD2 Code P0121 Jeep 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 Jeep
Symptoms of a P0121 Jeep 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 Jeep
A code P0121 Jeep 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 Jeep:
,2013 Jeep Wrangler Unlimited Moab,2013 Jeep Wrangler Rubicon 10th Anniversary,2013 Jeep Grand Cherokee Trailhawk,2012 Jeep Wrangler Unlimited Altitude,2012 Jeep Wrangler Freedom Edition,2012 Jeep Wrangler Dragon Concept,2012 Jeep Wrangler Call of Duty MW3,2012 Jeep Wrangler Arctic,2012 Jeep Wrangler,2012 Jeep Liberty Arctic,2012 Jeep Grand Cherokee SRT8,2012 Jeep Grand Cherokee Concept,2011 Jeep Wrangler Mojave,2011 Jeep Wrangler Call of Duty Black Ops,2011 Jeep Wrangler,2011 Jeep Patriot,2011 Jeep Grand Cherokee UK Version,2011 Jeep Grand Cherokee,2011 Jeep Compass,2009 Jeep Wrangler Unlimited EV,2009 Jeep Patriot EV,2008 Jeep Wrangler Unlimited UK Version,2008 Jeep Wrangler UK Version,2008 Jeep Renegade Concept,2008 Jeep Patriot Back Country Concept,2008 Jeep Liberty,2008 Jeep Grand Cherokee S-Limited UK Version,2008 Jeep Grand Cherokee Overland UK Version,2008 Jeep Grand Cherokee,2008 Jeep EV Concept,2008 Jeep Cherokee,2007 Jeep Wrangler Unlimited,2007 Jeep Wrangler Rubicon,2007 Jeep Trailhawk Concept,2007 Jeep Patriot UK Version,2007 Jeep Patriot,2007 Jeep Grand Cherokee UK Version,2007 Jeep Grand Cherokee SRT-8 UK Version,2007 Jeep Compass UK Version,2007 Jeep Compass,2007 Jeep Commander UK Version,2006 Jeep Grand Cherokee SRT8,2006 Jeep Commander 4×4 Limited 5.7 HEMI,2005 Jeep Wrangler UK Version,2005 Jeep Patriot Concept,2005 Jeep Liberty Renegade 3.7,2005 Jeep Liberty CRD Limited,2005 Jeep Hurricane Concept,2005 Jeep Grand Cherokee 5.7 Limited,2005 Jeep Gladiator Concept,2005 Jeep Compass Concept,2005 Jeep Cherokee UK Version,2004 Jeep Wrangler Unlimited,2004 Jeep Rescue Concept,2003 Jeep Treo Concept,2003 Jeep Grand Cherokee UK Version,2003 Jeep Cherokee UK Version,2003 Jeep Cherokee Renegade,2002 Jeep Willys2 Concept
Note:
1. The list of automotive Makes at the right edge of the screen. The currently selected ODB-ii codes is for the Jeep makes.
2. Look up the other OBD II Trouble Codes, please use the search box. Enter the 5 character trouble codes in the search box and submit the search.
3. Don’t assume a particular OBD-II code means the same for other auto manufacturers as there are many makes specific codes in use.
4. If your OBD-II trouble codes are for a different car, select that vehicle series before searching for the diagnostic codes because not all OBD2 codes used by one manufacture are used by the other makes.
5. The information contained on this site is presented for informational purposes only. We are not responsible for any actions you take on your vehicle. If you have any doubt as to repairs on your vehicle, please contact your technician.