So i drove my 2019 straight to the dealership when had loss of power bogging and dash lighting up... seen its the tube sensor thing going to clutch fa

[Grumpz]

Yes,

So the truck was taken to the dealership on August 18th. Have they made a diagnosis yet?

Bad fan clutch caused short in wiring and also blew the oil pressure sensor. Not the best engineering design in the world, that's for sure

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[Grumpz]

After looking at this pic, I thought I would go out to the truck and physically look at the clutch with engine running.

The whole assembly spins with the module remaining semi rigid, some very slight movement rocking back and forth but mostly rigid, I very carefully reached down and moved it side to side.
No grabbing or any resistance noted.

Note: An easy way to mentally picture this is grab the module and spin the clutch

I was determined to come up with a reason for this to fail and rip the harness apart.

I have come up with some possible failure points and makes logical sense.

That module is sandwiched between the backside of the nut and backside of the hub.
With engine off or running you can rotate the module side to side, so it is free-floating.
I am assuming it is a solid shaft between the nut and hub with a metal raceway and or a bearing and race that the module is riding on. Would have to see one apart to be sure.

I can see that that over time, the raceway can wear and gall and cause friction, thus create a grabbing effect on the module as it will want to spin with the rest of the unit.
Now, if this wear gets bad enough, I can see the module now being able to rock front to back and grabbing the back side of the hub and the module wedging itself in between the nut and hub, thus being the big rip of the hose and harness as now it will really want to spin with the rest of the unit.

Another possible is Bearing wear on the hub itself, if the hub bearing gets wear it will let forward and aft movement of the hub and thus let the hub rock backwards toward the nut and wedge the module in between, making it rotate with the unit.

Basically, in a nutshell the module is being pinched or wedged in between the nut and hub and when that happens the module will want to spin, the rubber hose is installed to allow for friction movement of the module.

Modification Options: Hmm

1. If you were to install a rigid line / bracket in place of the rubber hose, might cause more stress on the raceway and physically break the plastic.

2. Reroute the wire harness off of the hose, will not help as the module (in a failure) described above will still spin and pull on the harness and connector anyway.

By using this borrowed pic from earlier post let's look at exact what the hose does for the module.


The Fan spins clockwise (as you are sitting in the truck) so the module also want to spin clockwise by the small amount of friction that is created by the rotation of the fan as its riding on the raceway.

Note the position and routing of the hose, it is there to absorb that friction resistance and keeps the module in place.

Now if the hose breaks the absorption is taken away and the module will want to spin.
or
If any failures noted above will put more stress on the hose forcing it to break
Now the wire harness is still attached to the hose and the module spins ripping the harness because it is clamped to the hose.

I do see one option to possibly help the wire harness and I have a strong hunch that this is where the harness damage is occurring and that is the first clamp on the route from the connector.
That looks like a stress point on the harness.
And I am fairly certain that is where the wiring is being damaged, due to the fact that when that hose flexes the wire harness will flex with it, and the area that is going to flex the most is right at the clamp.
and the hose stress point is where the small bend in the hose at the point where it clamps to the engine side, I feel that this is where the hose will break as this point will absorb the most force against it on the nipple connection for the hose.

So, the only solution I see to possibly save the wire harness is to either take the harness out of that clamp and leave in unclamped or zip tie it farther up the hose. It would allow more movement of the wire harness if the module were to spin clockwise and also eliminate the flex stress point at that clamp.
This is just my observation of this and possible solution to full wire harness damage.

I hope my rambling makes some sense for everyone.

Very detailed and, I'm assuming, accurate description of what most likely happened. Very concerning that it failed after 20k miles. I'm probably going to try and set it up in a way that gives the harness a little bit of play but not too much. Thanks for the tips. Not the best engineering design I've ever seen lol that's for sure

 

[Muffin1]

@Grumpz
Seeing you have a '19 do you have a ext warranty?
Since its' not falling under the powertrain portion do you happen to know if it would be covered under B2B portion?
This sucks that owners are going to be on the hook for this obviously poor and over engineered design. I have a ext warranty and am going to check the covered parts section

EDIT;
According to the parts covered list with Fords Premium Care ext warranty, • Radiator Fan (Clutch or Motor • Radiator Fan Relay , ) would be covered. Although not seeing oil pressure sender specifically, which you mentioned was a damaged part, although coolant temp sensor is covered.
Ahhh very confusing

 

[Jason B]

You made me smile with the shake test and brought back memories. A very long ti,e ago in a land far away IBM made punch card readers (Model 059) that used reed relays. These relays were contained in a sealed glass tube maybe a, 1/8" in diameter and 3/4" long. They were fragile to say the least, and there were whole banks of these relays in the card reader. The 059 look almost identical to the 029 below.


Those relays were notorious for sticking, and I'd get a call to come repair the machine. As soon as I'd remove the back cover the slight vibration would untack the relay contacts and the machine would begin to operate normally. I tried all manner of tactics and strategies to pinpoint the problem relay, but nothing worked. Finally, I resorted to simply lifting a corner 1/4" off the floor and dropping the 059. Worked every time!

For those of you who wonder what a punched card is... Here's a picture of one. The test pattern has been run on this one 80 column card. This was high tech in the 1960-1970's.


The "shake test" tried and proven for many years! Now back to our regularly sheduled programming! (pun intended )

We used to call that 'vibration reset'.

It is all anecdotal evidence. I've had my Ranger for almost 4 1/2 years and had zero electrical issues, and I know there are others on here with similar experiences. But that is a very small percentage of owners as is one tech.

As many people have said - people don't typically post on forums that they love their vehicles - they post on forums when they have problems, so you typically get a distorted view of things if you are attempting to use that as a gauge as to how many issues any vehicle has.

Probably happens as much as "defective transmissions".

 

[Racket]

We used to call that 'vibration reset'.



Probably happens as much as "defective transmissions".

Summon the lawyers - I smell a class action lawsuit!

You get $1.75! You get $1.75! And You get $1.75!

 

[Grumpz]

@Grumpz
Seeing you have a '19 do you have a ext warranty?
Since its' not falling under the powertrain portion do you happen to know if it would be covered under B2B portion?
This sucks that owners are going to be on the hook for this obviously poor and over engineered design. I have a ext warranty and am going to check the covered parts section

EDIT;
According to the parts covered list with Fords Premium Care ext warranty, • Radiator Fan (Clutch or Motor • Radiator Fan Relay , ) would be covered. Although not seeing oil pressure sender specifically, which you mentioned was a damaged part, although coolant temp sensor is covered.
Ahhh very confusing

I have a standard factory warranty, currently only power train is left. That covers the oil pressure sensor, but im out 1200 bucks for everything else. Not sure if they're planning on putting any warranty on the new parts or labor. Might be looking at getting a Toyota if it gives me anymore major problems ? this is my 3rd Ford and the engines and transmissions have always been pretty decent but they seem to have weird and quirky issues, and some quality problems. Just my personal experience though.

 

[airline tech]

I have a standard factory warranty, currently only power train is left. That covers the oil pressure sensor, but im out 1200 bucks for everything else. Not sure if they're planning on putting any warranty on the new parts or labor. Might be looking at getting a Toyota if it gives me anymore major problems ? this is my 3rd Ford and the engines and transmissions have always been pretty decent but they seem to have weird and quirky issues, and some quality problems. Just my personal experience though.

For clarification the Variable Oil Pressure Control Solenoid in the circuit does not read oil pressure.
It only Controls the pressure.
The PCM sends information to the Control Solenoid as to what the oil pressure should be and adjusts the porting of oil (by-pass) within the oil pump.
When in by-pass it is by-passing oil back into the oil pan.

So, the Solenoid would be more tied with the Oil Pump or Control, if looking at the Warranty fine print.

So, after digging into the wiring circuit power feed, I can see the reason for a P0034 Turbo Charger By-Pass valve and the oil pressure message (Low-Oil Pressure)

Power is fed in this order from the fuse

1. Fuse
2. Vabin Heater Coolant Pump
3. Trans Fluid Heater Coolant Cont Soleniod

To a 3-Way (Wire Splice)

4. Turbocharger By-Pass Valve
5. Variable Oil Pressure Cont Solenoid
6. Cooling Fan Clutch

So, if you look at the circuit in reverse, the first 2 items are the Oil Press Cont Solenoid and Turbocharger By-Pass.
With a short circuit at the Fan Clutch, these are the first things that would code due to loss of power.
As this may explain the reason for a single P0034 (Turbo Charger By-Pass) as it would one of the first sensors to see loss of power.
and depending on the PCM programming these would be a high priority code and generate first.

 

[TJC]

The utter foolishness and incompetence in this design is that if any of the 5 unrelated functions fail causing the fuse to blow, all systems cease to function. Losing a cooling fan clutch should not affect the turbo or oil pressure system.

I do not know a single engineer who would approve a design like this! NOT ONE!

 

[Grumpz]

The utter foolishness and incompetence in this design is that if any of the 5 unrelated functions fail causing the fuse to blow, all systems cease to function. Losing a cooling fan clutch should not affect the turbo or oil pressure system.

I do not know a single engineer who would approve a design like this! NOT ONE!

This!!! I am not an engineer but I work with engineers and I could never see where that would be approved...maybe shaving some money off of cost by running everything together...but still. How'd that get approved?!?! I was in limp mode, trying to get home with no power to anything, even the AC, in 95 degree weather, and all because of the fan clutch ?

 

[Grumpz]

For clarification the Variable Oil Pressure Control Solenoid in the circuit does not read oil pressure.
It only Controls the pressure.
The PCM sends information to the Control Solenoid as to what the oil pressure should be and adjusts the porting of oil (by-pass) within the oil pump.
When in by-pass it is by-passing oil back into the oil pan.

So, the Solenoid would be more tied with the Oil Pump or Control, if looking at the Warranty fine print.

So, after digging into the wiring circuit power feed, I can see the reason for a P0034 Turbo Charger By-Pass valve and the oil pressure message (Low-Oil Pressure)

Power is fed in this order from the fuse

1. Fuse
2. Vabin Heater Coolant Pump
3. Trans Fluid Heater Coolant Cont Soleniod

To a 3-Way (Wire Splice)

4. Turbocharger By-Pass Valve
5. Variable Oil Pressure Cont Solenoid
6. Cooling Fan Clutch

So, if you look at the circuit in reverse, the first 2 items are the Oil Press Cont Solenoid and Turbocharger By-Pass.
With a short circuit at the Fan Clutch, these are the first things that would code due to loss of power.
As this may explain the reason for a single P0034 (Turbo Charger By-Pass) as it would one of the first sensors to see loss of power.
and depending on the PCM programming these would be a high priority code and generate first.

Yes and luckily with that blown it still flows oil through the engine mechanically I believe, which saves the engine from oil starvation. Still an odd setup though

 

[Muffin1]

This!!! I am not an engineer but I work with engineers and I could never see where that would be approved...maybe shaving some money off of cost by running everything together...but still. How'd that get approved?!?! I was in limp mode, trying to get home with no power to anything, even the AC, in 95 degree weather, and all because of the fan clutch ?

With the simplicity of electric fans why not is the question, clutch fans are noisy, not efficient
(drag on the motor) and this particular design is overly complicated.

 

[TJC]

I believe these decisions are all being made to meet ever tightening EPA fuel standards. Those same standards are driving the prices of ICE vehicles higher each year. I fear this is how the gov is going to move the population out of private ownership of autos.

Not today or tomorrow, but 10-15 years from now.

 

[Grumpz]

I believe these decisions are all being made to meet ever tightening EPA fuel standards. Those same standards are driving the prices of ICE vehicles higher each year. I fear this is how the gov is going to move the population out of private ownership of autos.

Not today or tomorrow, but 10-15 years from now.

Yeah its been very noticeable for me on newer motorcycles. Euro 5 specs are forcing manufacturers to use bigger engines to get the same performance since the engines are so corked up and ran a bit lean. I'm rooting for hydrogen so I don't have to get rid of the vroom vroom engines completely ?

 

[airline tech]

Yes and luckily with that blown it still flows oil through the engine mechanically I believe, which saves the engine from oil starvation. Still an odd setup though

I dug into the Pinpoint test for the solenoid, and with it disconnected, (same as power drop with blown fuse) Oil Press should rise by 40 PSI, so this would be the fail-safe.

So, the codes and messages relating to oil pressure (in this case) would be for oil pressure control, and you should be getting unaltered oil pressure from the mechanical oil pump.

 

[TJC]

Whats the oil pressure range?

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