Overheat Code on Startup - Where is the Engine Temperature Sensor?

[XionUAV]

This is the FX4 rebuild project. I'm getting an overheat error on startup and the temp gauge is pegged. This also keeps the vehicle from revving above about 2k RPM.

I have poured over the thousand pages of shop manual and cannot locate a temperature sensor to save my life. It's mentioned for the 2.0L Euro motor but not for the 2.3L. It doesn't even show one or mention one in the cooling system diagram.

Can someone tell me where it is? Any help would be appreciated. Thank you.

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[ctechbob]

For whatever reason we have CHT sensors and not coolant sensors.

 

[RangerBill]

This is the FX4 rebuild project. I'm getting an overheat error on startup and the temp gauge is pegged. This also keeps the vehicle from revving above about 2k RPM.

I have poured over the thousand pages of shop manual and cannot locate a temperature sensor to save my life. It's mentioned for the 2.0L Euro motor but not for the 2.3L. It doesn't even show one or mention one in the cooling system diagram.

Can someone tell me where it is? Any help would be appreciated. Thank you.

The shop electrical diagrams show a coolant temperature sensor ECT.

 

[XionUAV]

There's conflicting information because I finally found this in the manual. Says it's behind the splash panel through the passenger fender well. That makes no sense since it's mostly exhaust on that side.

 

[XionUAV]

The shop electrical diagrams show a coolant temperature sensor ECT.

I just took a look and there is no sensor in that area. Take a look at the pic. The engine is still filthy from being at the body shop for a year. I'll clean it once a few more things are sorted.

 

[XionUAV]

For whatever reason we have CHT sensors and not coolant sensors.

And there it is. I'll order a new one and give it a go. Thanks for the assist.

 

[ctechbob]

If you are standing in front of the truck with your stomach on the front bumper, it is on the left, underneath a heat shield.

Beat me to it.

 

[XionUAV]

If you are standing in front of the truck with your stomach on the front bumper, it is on the left, underneath a heat shield.

Beat me to it.

It's pretty obvious if you know what you're looking for.

Curious about that price, though. I'm seeing them from around $25 to $45.

EDIT: Just went to Ford Parts like you show and ordered it for pickup at a local Ford dealership. Total price $6.46.

Another mystery of the Ford Parts universe.

 

[ctechbob]

It's pretty obvious if you know what you're looking for.

Curious about that price, though. I'm seeing them from around $25 to $45.

It was off of

https://parts.ford.com/shop/en/us

Plugged in my zip and it said I was shopping my local dealer. Dunno what it would be with shipping.

 

[airline tech]

OK, I have to dig into this one, 1st all descriptions in the manuals show 2ea sensors.
1. ECT - Used for Fuel Control & Clutch Fan & Open Loop Control
2. CHT - Used for Temp Monitoring and Gauge Indication & Closed Loop Control

Both sensors have the ability for the PCM to command LIMP Mode, which is what you currently have. (Fail Safe-Cooling)

But however, in the Pinpoint Tests - there is a note
On applications that do not have an ECT, the CHT is a dual purpose

Now there is a difference on this between the trims and that is your IPC cluster, lower trims have the (analog gauge) and the Lariat has a (digital gauge)
This may be the difference, and the confusion IDK.
So, I am going to physically check on mine to see if I have both or just a single sensor.
as this is confusing and needs some clarity.
and then you have diagrams like posted above that point to the location of the CHT and call it the ECT

But for your issue, have you cleared the code - P1285 as I assume this code is generated
If you have this code, the PCM fail safe strategy is to peg the gauge, when this happens the PCM also deactivates 2 cylinders and limits RPM.

I have a feeling if you clear the code, the temp indication will come back to normal

So, just because its pegged, does not mean the sensor is faulted.

Did you properly bleed the system?
This would be my first thing to check
Especially since it's got a new radiator, there is most likely lots of air in the system

 

[airline tech]

Another possibility is a damaged wire on that VREF circuit

 

[Loweredon33s]

It’s on the back of the head.

 

[RangerBill]

Forscan shows a readout for ECT and CHT sensors for my 2019 Ranger Lariat. The CHT reading increased more rapidly than the ECT reading, but both seemed to be valid and both increased as the engine warmed up.

 

[airline tech]

Screenshot taken from a Youtube video for a 2020 Ranger ECT Replacement video
Located just above the Exhaust Manifold - RH Wheel Well via removing the access cover.

So, this at least confirms that there is one installed, the unknow form the video is what trim level he has.

Note: In the video he states the reason for replacement is pegged temp gauge, however in the comments section he states this did not fix the issue, he had air in the system and needed to bleed the system- so this backs up my first thought and theory on the pegged gauge.

For Ref: Here is the link to the video

New Valvoline Restore & Protect (youtube.com)

 

[XionUAV]

OK, I have to dig into this one, 1st all descriptions in the manuals show 2ea sensors.
1. ECT - Used for Fuel Control & Clutch Fan & Open Loop Control
2. CHT - Used for Temp Monitoring and Gauge Indication & Closed Loop Control

Both sensors have the ability for the PCM to command LIMP Mode, which is what you currently have. (Fail Safe-Cooling)

But however, in the Pinpoint Tests - there is a note
On applications that do not have an ECT, the CHT is a dual purpose

Now there is a difference on this between the trims and that is your IPC cluster, lower trims have the (analog gauge) and the Lariat has a (digital gauge)
This may be the difference, and the confusion IDK.
So, I am going to physically check on mine to see if I have both or just a single sensor.
as this is confusing and needs some clarity.
and then you have diagrams like posted above that point to the location of the CHT and call it the ECT

But for your issue, have you cleared the code - P1285 as I assume this code is generated
If you have this code, the PCM fail safe strategy is to peg the gauge, when this happens the PCM also deactivates 2 cylinders and limits RPM.

I have a feeling if you clear the code, the temp indication will come back to normal

So, just because its pegged, does not mean the sensor is faulted.

Did you properly bleed the system?
This would be my first thing to check
Especially since it's got a new radiator, there is most likely lots of air in the system

You, sir, are a stud.

When I looked at the DTC's using FORscan, it had the Ambient Air Sensor error and a "P" error that I regretfully did not document. I did save the profile though so maybe the codes are logged somewhere?

However, I just went out and quickly looked at the codes using Torque and a Bluetooth dongle. There were a bunch of them. Most were "Powertrain." Cleared them and was astounded that on the next startup the gauge was normal, or cold. Brilliant! Obviously it will need to run for a while to see if the codes come back or not.

Regarding the coolant, it took somewhere over 2 gallons but has only run for a total of 10 minutes at idle to calibrate the new throttle body. It still needs a proper bleed.

One more question that might need a separate thread, unless it's been covered before. I do try to search the threads but the results can be all over the place.

The steering rack is cracked around the case with a gap of a good 2mm. I sourced a used rack but at the time did not realize it needs to match the vehicle trim level. I've read that programming the electronics in the rack can only be done by the dealer, and they won't do it unless it's a new rack and they install it. Others I've asked didn't know if FORscan was capable of programming the rack or not. I honestly can't remember what the trim level was of the donor vehicle.

Therefore unless it's known for sure that FORscan can program the rack for the proper trim level, XLT FX4 in my case, I'm considering swapping the electronics boxes on the racks, if that's even possible. That project is a few rows down the current list but the rack will definitely need to be sorted before the Ranger goes out on the road for any test drives.

Thank you to everyone for your input and help.

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