My jeep is throwing a p0339 code. I replaced the crankshaft position sensor and the cel went away. I then went out of town and its doing the same thing. Jeep starts bucking and stalling out. Any clue what else it could be?
P0339 --- A rationality error has been detected for intermittent loss of crankshaft position sensor.
Since it is an intermittent problem (which would explain the bucking) I would check the connections at the sensor & at the PCM as well as the wiring between. You don't give the yr so I can't be more specific as to where the wires connect at the PCM.
Sorry, it's a 2005 6 cyl
First check all connections at the sensor then the PCM then the wiring between.
The signal wire from the sensor to the PCM is brown/light blue. It is on the bottom row in the C-2 connector, which is 2nd from left when facing firewall & should be orange. Make sure that pin & socket is not loose or corroded.
The 5v supply wire is pink/yellow & also goes to the C-2 connector, bottom row.
That also supplies 5v to the TPS & since you aren’t getting a code for that I would guess it is more likely in the signal wire.
I have changed the crankshaft position sensor with OEM at least 1 year ago as well as the TPS with OEM 2 weeks ago and my wifes jeep was bucking while driving for the last week, then gave me the blinking check engine light (which means misfire, right?) then when I returned home I checked the codes using the key on off 3 times method and was given the p0339 (crankshaft position) and p0122 (TPS) codes. havent driven it in a week, pretty much came home and parked it. since i have replaced both of these sensors and this vehicle is my wifes daily driver and doesnt go on trails/offroading, i have a feeling the sensors are still good and that something else is on the fritz.
will you help me with my issue please? thank you in advance
when i replace these sensors, i am supposed to do something in particular with the computer afterward to tell it that i changed the sensors? the reason i ask is because i havent done anything special to the computer to notify it that i changed the sensors, i just get in and drive with the thought that the computer will learn that a new sensor is in there over the course of the driving.
The P0339 is a rationality error has been detected for intermittent loss of crankshaft position sensor & the P0122 is throttle position sensor input below the acceptable voltage range. The input voltage is from a 5v supply at the PCM which is for a bunch of other sensors as well so I would assume the 5v supply is good at the PCM. You should check that that voltage is present at both sensors & that both are getting grounded. Then I would check the wiring starting with the C-2 (orange) connector at the PCM. Pull that connector & carefully inspect the pins on the PCM & the female terminals on the connector. Pay special attention to the lower 2 rows. Pin # 29 is the 5v supply & pin # 35 is the CKP signal & pin # 21 is the TPS signal.
Here is how to test the TPS from the FSM:
THROTTLE POSITION SENSOR
The 3–wire Throttle Position Sensor (TPS) is mounted on the throttle body and is connected to the throttle blade.
The TPS is a 3–wire variable resistor that provides the Powertrain Control Module (PCM) with an input signal (voltage) that represents the throttle blade position of the throttle body. The sensor is connected to the throttle blade shaft. As the position of the throttle blade changes, the resistance (output voltage) of the TPS changes.
The PCM supplies approximately 5 volts to the TPS. The TPS output voltage (input signal to the PCM) represents the throttle blade position. The PCM receives an input signal voltage from the TPS. This will vary in an approximate range of from .26 volts at minimum throttle opening (idle), to 4.49 volts at wide open throttle. Along with inputs from other sensors, the PCM uses the TPS input to determine current engine operating conditions. In response to engine operating conditions, the PCM will adjust fuel injector pulse width and ignition timing.
The PCM needs to identify the actions and position of the throttle blade at all times. This information is needed to assist in performing the following calculations:
Ignition timing advance
Fuel injection pulse-width
Idle (learned value or minimum TPS)
Off-idle (0.06 volt)
Wide Open Throttle (WOT) open loop (2.608 volts above learned idle voltage)
Deceleration fuel lean out
Fuel cutoff during cranking at WOT (2.608 volts above learned idle voltage)
A/C WOT cutoff (certain automatic transmissions only)
Here are the wiring pin outs for the 2 sensors.
Thank you for replying Rubi 4 my mrs
could you recommend a tool to check the voltage and grounds? im very new to buying tools to diagnose/test electronic equipment.
is the PCM above the battery with 4 similar connectors connected to it? YES
is c2 the second one when you count from left to right? YES
if what i think is the PCM is the PCM, how are those connectors removed? SLIDE RED TAB BACK TOWARDS HEADLIGHTS THEN PRESS BLACK TAB AND PULL CONNECTOR TOWARD HEADLIGHT
An inexpensive volt-ohm, also called a multi-meter will do just fine. They will test a/c & d/c voltage, resistance (ohms) & continuity. Harbor Freight always has them for less the $10, sometimes free with any purchase. If you go in there are usually sale flyers in there & may even have a 20% off coupon.
Here is a link, I’m sure there is a store near you.
Digital Multimeter - 7 Function, w/ Backlight
A test light is also handy for circuit testing.
Google how to use & you will find good info if needed.
Yes, 4 connectors if you have auto trans
Yes, 2nd when facing it. oxoo
I think that is correct. I haven’t had to actually remove any on mine but that sounds right.
Here is a link to FSMs but only up to 2003. The 1st chapter in the wiring section has good info on removing connectors & using a meter & for that section the 2003 is the same as yours.
See online read only FSMs here:
Jeep Knowledge Base
You may have to go to the bottom of the page & pick Jeep Resources & online manuals if it directs you to home page rather than the knowledge base.
Pick your model & year then on the drop down menu pick the chapter you need.
i'll pick up the multimeter and circuit tester tomorrow after work. thanks for pointing me in the right direction.
i have a 05 FSM.
what year is your rubicon?
thanks again. ill talk to you tomorrow.
I had the same problem/code on my son's 97 TJ. I replaced the throttle position sensor and that fixed it. No problems since then.
It's in my sig, '05 Unlimited Rubicon.
UPDATE: The light has turned off. All I did was drive it to work. I will report back when it comes back on.
Thank you for everything Rubi 4 my mrs, I went and picked up the multimeter and circuit tester today. I will educate myself on how to use them.
|All times are GMT -5. The time now is 07:09 AM.|