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Hey Guys-

So suddenly, my oil pressure indicator light has started to come on. I checked the oil, it is still only about 1000 miles old and is at the correct capacity, and their are no leaks. After doing some research, it looks like the Oil pressure sensor unit may be the issue. I have a 2006 Commander 3.7L, but I have having issues locating the sensor. From what I can see when looking under the hood, the sensor is directly above the oil filter with 1 wire coming out of it. It is very hard to get to and I was able to fit my camera down there to take some pics, just so someone can confirm this is in fact the Oil pressure sensor and has some tips on how to remove it? I know I would need a larger size deep socket.

Everything I'm reading seems to say to get to the sensor from under the car but I really don't see how that would even be possible. And I also keep reading about a red tab on the electrical connector, but I only see 1 white button (as seen in the pics below).

Any info on if this is the correct location for the sensor?

Thanks in advance!
 

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Looks very corroded, you might try cleaning up the connector first. Looking at the service manual for the 3.7 it shows the sensor as in your pictures so you found it. The tab to release the connector is probably on the back side of the picture you posted. Looks like fun, but from underneath should be the way to get it. Should be a fairly inexpensive repair at a auto repair shop.
 

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From the service manual - to remove the sensor. Very basic and not a lot of help:)
1. Disconnect the negative cable from the battery.​
2. Raise vehicle on hoist.​
3. Remove front splash shield.​
4. Disconnect oil pressure sender connector (4).​
5. Remove the pressure sender (2).
 

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Or, you're oil pressure light is coming on to tell you have a oil pressure below the spec. Don't know the figure on the Commander, on most Chrysler vehicles its below 10PSI +/- 4PSI.

The first trouble shooting step in the manuals will tell you to connect a mechanical oil pressure gauge to the engine and confirm the actual oil pressure. Those gauges are expensive and it takes time to connect it.

When and under what conditions the light comes on can be telling, whether you truly have low oil pressure or if the warning light circuit or sensor is malfunctioning.

Remember, as the engine wears the gap between moving parts increases and thus oil pumped into those gaps to lubricate can flow through the larger gap, the oil pressure will drop, the pump itself wears as well. Low oil pressure can also be an indication of engine wear. Low or high oil pressure can be a symptom of malfunctions, such as debri in the oil passages clogging the oil flow, a clogged oil filter, a leak, etc....

The colder the engine (thus the oil), the more viscous the oil and it thins to less viscous with more heat. Thus the oil pressure should be highest when cold and lowest when warm, and the oil pressure goes even lower if the engine is running hot or overheating. The lower the rpm the slower the pump moves, thus lower oil pressure.

The engine at full operating temp, at idle, in gear, thus hot at its lowest rpm, the oil pressure should be 17PSI or more. As rpm increases, the oil pressure should increase, to 55PSI or more. The FSM sometimes has specs to check oil pressure, and its typically the hot, idle in gear spec and an RPM spec where the oil pressure should be higher than when you hit that rpm, maybe several of those.

A cold engine, the colder the oil, first start on a cold morning should be high oil pressure. A hot engine, as in overheating will lower the oil pressure and could light the light.

So if the oil pressure light comes on consistently in conditions when you would expect the engine to have its lowest oil pressure, and never lights when you expect the engine would have higher oil pressure, it could be a good light telling you have low oil pressure.

BUT, if the oil pressure light stays out in conditions when you would expect the lowest relative oil pressure, and comes on in conditions when the oil pressure should be relatively higher, the sensor or circuit is a possibility to consider. Foreign debri in the engine oil passage or pick-up screen could cause true low oil pressure in those conditions so don't rule it out.

OK, the system works simply by a light on the dash that has a 12VDC power supplied to it all the time, the ground wire for the bulb runs down a single wire to the sensor. When the sensor sees less than the specified pressure, it closes a switch to complete the ground circuit for the light and light the light.

A bad pressure switch/sensor could cause the light to come on erroneously, an intermittent short circuit in the circuit could case this as well. Oil or contaminants in the connectors can also do it. Again, if the light comes on when it should if you had low oil pressure, don't rule out an oil pressure problem with the motor. If the oil pressure light is coming on at times it shouldn't and NOT when it should if you had low oil pressure, then suspect the sensor or its circuit.

The "White Tab", that is NOT a tab to unlock the connector in your photo, the connector can be used as a 2 wire or 1 wire connector, in your case, it only needs 1 wire, and that white square in the photo is just a plug in the connector to fill the opening for a 2nd wire. The red plastic slide clip is on the side of the connector, NOT top. Usually it has to be slide/forced to slide sideways to unlock the main clip, that you have squeeze as you pull the connector off.
 

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OK, the system works simply by a light on the dash that has a 12VDC power supplied to it all the time, the ground wire for the bulb runs down a single wire to the sensor. When the sensor sees less than the specified pressure, it closes a switch to complete the ground circuit for the light and light the light.
First it runs on 5 Volts not 12, and then it gets even more complicated - from the service manual


The PCM continually monitors the engine oil pressure sensor to determine the engine oil pressure. The PCM then sends the proper engine oil pressure messages to the instrument cluster. For proper diagnosis of the engine oil pressure sensor, the PCM, the CAN data bus, or the electronic message inputs to the instrument cluster that control the low oil pressure indicator, a diagnostic scan tool is required.​
 

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Our old Liberty did the same thing. It's not hard to get to and you'll probably see where it's been leaking also. They are cheap and if the engine isn't making any strange noises that should clear it up for you.
 

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Chrysler oil pressure sensors are known to fail quite regularly. On commanders the 5V circuit runs through the sensor so many times a failed sensor will cause several other DTC codes to show up due to cutting off the 5V supply to other sensors in the circuit. This is what mine did when it failed on my 5.7 Hemi.
 

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Hey Guys-

So suddenly, my oil pressure indicator light has started to come on. I checked the oil, it is still only about 1000 miles old and is at the correct capacity, and their are no leaks. After doing some research, it looks like the Oil pressure sensor unit may be the issue. I have a 2006 Commander 3.7L, but I have having issues locating the sensor. From what I can see when looking under the hood, the sensor is directly above the oil filter with 1 wire coming out of it. It is very hard to get to and I was able to fit my camera down there to take some pics, just so someone can confirm this is in fact the Oil pressure sensor and has some tips on how to remove it? I know I would need a larger size deep socket.

Everything I'm reading seems to say to get to the sensor from under the car but I really don't see how that would even be possible. And I also keep reading about a red tab on the electrical connector, but I only see 1 white button (as seen in the pics below).

Any info on if this is the correct location for the sensor?

Thanks in advance!
Did you get her fixed?
 
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