I have a CEL/Code P0117 on my '04 3.0 Ranger.It indicates that the coolant temp sensor is low voltage.....something like that...….

MY question is there a separate sensor that sends info to the PCM as well as 1 that sends temp info to the actual gage?

I have done some research and believe that there is only 1 sensor used in the 3.0...…

I have ordered a MOTORCRAFT sensor because it has long been known that Fords don't like aftermarket sensors....

Anyone have any experience with this code on the 3.0 engine?

 

There are Separate sensors for the ECT & dash gauge.
Make sure the ECM supplied 5 volt reference is present at the ECT sensor & that the electrical connector contacts & wiring to it are clean & sound & the connector is securely fastened. If all that is ok, then the sensor thermistor has likely gone out of range. Compare the resistance of the old one to the new one at ambient & hot temps.
Here is a trouble shooting link to follow if the problem turns out to be more than a faulty sensor. Just ignore the aggravating ads & scroll down to get the helpful trouble shooting info. https://www.obd-codes.com/p0117
Some trouble shooting thoughts for consideration, let us know how it goes

 

Thanks for this. Any idea where the sensor for the PCM is on the 3.0?

 

Looking at the engine from the front top, where the upper radiator hose connects to the engine, the ECT computer temp sensor is to the rear & at about the 2 o/clock/drivers side position, its the 2 wire sensor. The dash gauge coolant temp sensor is a single wire & at about the 10 o/clock/passenger side & to the rear of the upper radiator hose engine connection.
Since the code is for low voltage, if the ECM supplied 5 volt reference is present at the ECT connector, it suggests that the temp sensor thermistor resistance is too high at operating temp, so is sending the computer a lower than expected voltage for the engine operating temp.
You could warm the new sensor with a hair dryer & measure its resistance & do the same for the engine temp sensor & see if they measure about the same resistance with your DVOM.
If the dash temp gauge indicates the engine has been running colder than usually indicated, you might have a sticking open thermostat & that could cause a low voltage & you might have been seeing a drop in mpg, or drive-ability problems, so keep that in mind while trouble shooting the problem. Right now I'd guess the ECT sensor has gone out of calibration & is high resistance at operating temp, thus sending the ECM a lower than expected voltage. More thoughts for consideration, let us know what you find.

 

Thanks! (My Nephew actually replaced the 2 wire sensor awhile back with an aftermarket unit-again,I have ordered a brand new MOTORCRAFT sensor to replace it with.....

I will look for the single wire sensor now......I willmost likely replace IT as well because IMO my gage is reading a bit higher than I think it should.

On my '03 3.0 (different truck) I flushed the cooling system 9 ways to Sunday with a flush & fill kit,then ran cooling system cleaner followed by more flushing, then installed a 180* TStat.

IT runs cool, but not too cool here in Florida-I have been advised by several professional radiator & a/c shops that we can go to a 180* but no lower.....

I Did the same exact thing in the '04 3.0 plus my Nephew had just installed a brand new radiator, the '04 runs warmer-just a couple of hairs under half way on the gage......but NEVER goes any higher, no matter what the conditions.....

 

If the aftermarket ECT sensor checks out ok & the P0117 code turned up After the 180 deg thermostat was installed, you might find your answer there.

 

The truck came to me with the CEL on and NO Thermostat in it, my Nephew had taken it out when it slightly overheated before he replaced the radiator.....

I re-set the computer by unhooking the negative battery cable overnight after all the flushing and installing a brand new Gates HD 180* TStat.

The truck/engine sat here for nearly 2 hours idling after I installed the TStat and the correct Ford Gold coolant, never had the CEL come on.

I went on a short trip around town with it and the CEL came back on after less than 2 miles.....that's when I had the code read.....

I'm waiting on the MOTORCRAFT sensor, I'll install it and see where I'm at......hopefully this fixes it.....

I've got the same 180* TStat in my '03 3.0 Ranger and I've never had a CEL for any reason......

 

Some ECT temp sensor trouble shooting info you might find helpful

 

How is the trouble shoot going Supercab, 253 curious minds would like to know?

 

Good morning all, Well, I had a heck of a time finding/getting the correct sensor. (Again, I can only find the 1 sensor in the front of the engine)-IT has a 2 wire hookup, I finally gave in and installed a "BWD" brand sensor because no one, including Ford could seem to supply me with the correct sensor.
THIS sensor IS the one for the gage because I actually bought a Motorcraft unit which was the correct part number but wouldn't directly plug into the wiring harness, so I ended up filing off a raised up ridge on the sensor, I installed the sensor and at first it seemed to work ok, but then would peg out on HOT each time I started the engine.
This is when I gave in and bought the generic BWD (Borg-Warner) unit (Borg-Warner at least used to be a good quality part)
Is it possible that this 1 sensor (with 2 wires) serves not only the gage but the ECU as well?
Honestly, I cannot find another sensor where it was suggested I look.

Again, I also have an '03 Ranger Edge 3.0 and IT has the same sensor in the same location but it used only 1 wire going to it-IT IS a FLEX-FUEL 3.0 while the '04 3.0 in question here is NOT Flex fuel-(MY understanding is that there was NO flex fuel after 2003 in Ranger 3.0 engines anyway....

I honestly thought I had this problem licked because I took the '04 on an hour ride yesterday and it was fine for most of the ride, then started running a little rough at idle, then later in the day driving it again the check engine light came back on.....

 

UPDATE: I have compared my 2 Rangers; The 2004 Edge 3.0 and the 2003 Edge 3.0 Flex Fuel.

The 2003 has the 2 sensors; right where you said they would be PawPaw-1 that actually looks like an older model typical Ford sender that is for the gage-this one is threaded into the intake manifold just to the right of the thermostat housing. The other one is in the same place which is in front of the intake manifold and BOTH of these are 1 wire unit.

On the 2004 that I'm working with right now there is NO sensor threaded into the intake manifold just to the right of the thermostat housing. It has only the 1 sensor at the front of the intake, IT has 2 wires going to it.

So, 2 clearly different setups, I'm thinking that Ford did away with the dual sensors with 1 wire each and went to a single dual wire unit...…

There is also some info coming up saying that the ECU itself that MAY be bad/defective...……

How would I check the ECU? Anyone know?

 

Hold on, don't be too quick to condemn the ECM.
Have you performed the suggested reference voltage & sensor resistance tests? If so, post up the Numbers measured.
How was the engine coolant Temp sender threads sealed? If with something like PTFE ribbon dope, if too much was used, it could corrupt the ground connection & cause intermittent faulty readings that could confuse the ECM. Suggested sealant is something like Permatex/Loctite 565 liquid/anaerobic cure metal pipe thread sealant. It'll squeeze out between the threads as they are loaded when installed, so to give good electrical contact. Then in the absence of air will cure, so to seal the threads & hold the sensor in place with temp changes & vibration, while providing electrical contact.
More thoughts for pondering, keep us posted on your test findings.

 

You might query the guys on the Engine forum, to see if they can offer up some input on differences between those years on the engines in queston.

 

Thanks! I have this '04 all done and ready to sell and actually have someone interested and am holding them off until I can get this worked out.

I'm taking it to a VERY TRUSTED, VERY HONEST local shop that I have used before with GREAT success.

Just got to get it fixed so I can sell it and move on to my '03 which is almost done as well.

(I'm courting a snowbird couple with an ultra low mile '08 Sport Supercab that I really want when they come back down for the winter in November)