Does anyone know what this disconnected tube dangling off the bottom of my engine is?

[airline tech]

Ok - Then we need to isolate which side of the sensor is triggering the (Circuit High) code

The Exhaust Pressure sensor is on a VREF Circuit - LE135 and 3 sensors are on that circuit.
This is a 5-Volt Reference Circuit

1. Exhaust Press Sensor
2. Crankshaft Position Sensor
3. Cooling Fan Motor

The Signal Return for the Exhaust Pressure Sensor - is a shared return circuit - The following are on that circuit

1. Exhaust Pressure Sensor
2. EGRT (EGR Temp Sensor)
3. DPFE Sensor
4. CHT (Cyl Head) Temp
5. ECT (Eng Coolant Temp)
6. Rear O2 Sensor (Sensor Circuit)

So, any sensor or wiring in between - can be causing the issue

And we need to isolate - which side the issue is on - VREF or Signal Return

Ex Pressure Sensor - Connector (Ref)

Pin 1 = VREF
Pin 2 = Signal Return
Pin 3 - Signal to PCM

Key (ON)
Back-Probe - Pin 1 (VREF) to Battery Negative

You are looking for 5-Volts or very near it, if not within this range

Disconnect: (One at Time)
Cooling Fan Motor
Crankshaft Position Sensor

Did it move to 5-Volts?

Now (Shake) the harness between the PCM and these connectors

Does the Voltage (Fluctuate)?


If the VREF - Checks Good

Repeat for the - Signal Return - Key ON
Back-Probe - Pin 2 to Battery Negative (Ex Pess Sensor)
Now you are looking for Voltage Drop and any bleeding voltage into the circuit

The reading should be - 20 Millivolts or less - and disconnect (one at a time)

1. EGRT
2. DPFE
3. CHT
4. ECT
5. Rear O2

Perform the same (Harness) shake test and note any fluctuation on the meter

I feel that this is the problem circuit and the Throttle Position and com codes are secondary codes related to the above.

I noted no codes for the - Cooling Fan (VREF) feed and no codes for the other sensors on the signal return - that does not rule them out

Hopefully - the above wiring checks will reveal something and give a direction; I have a hunch that the PCM was condemned bad - due to this issue.

But this is a start anyway and where I would dive first and with it being unknown how much coolant entered the exhaust system - it could have taken out any of the exhaust related sensors.

Post you findings - and we can go from there

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[airline tech]

I should add - being that this was deleted from newer trucks

1. Add to the VREF (LE135) - The Crankshaft Pressure Sensor as you have a 2019 (its installed)

 

[airline tech]

I think it may be good idea - (for confirmation) to move outside the box and check all the PCM Grounds

The PCM has (4) Ground Wires that feed into (G117) and G117 also has via (splice) the Brake Pedal Position Switch

Check this (Ground Point) G117

Check the contacts at pins 96-97-98 and 99 on C175B

If you can get the cover off - Key (ON) and back-probe each pin to G117 (Voltage Scale)
Red Lead to (Pin) - Black Lead to G117
and
Then check G117 to Battery Negative

You want (Near-Zero) readings

This is to ensure that the PCM is providing a good ground for the signal return circuits

also check - since you are here -
Check all 3 PCM Power Feeds

C175B - Pins 100-101-102

This will verify we have good power to the PCM itself @ all 3 pins

I truly suspect the issue lies in the Singal Return or Ground path as being the most likely.

This is just me - Brainstorming and thought about the PCM grounds, more so the G117 and the PCM connectors were disturbed during engine removal - the contacts can easily be pushed in or damaged

Hopefully - you can get it isolated

 

[RangerBill]

I think it may be good idea - (for confirmation) to move outside the box and check all the PCM Grounds

The PCM has (4) Ground Wires that feed into (G117) and G117 also has via (splice) the Brake Pedal Position Switch

Check this (Ground Point) G117

Check the contacts at pins 96-97-98 and 99 on C175B

If you can get the cover off - Key (ON) and back-probe each pin to G117 (Voltage Scale)
Red Lead to (Pin) - Black Lead to G117
and
Then check G117 to Battery Negative

You want (Near-Zero) readings

This is to ensure that the PCM is providing a good ground for the signal return circuits

also check - since you are here -
Check all 3 PCM Power Feeds

C175B - Pins 100-101-102

This will verify we have good power to the PCM itself @ all 3 pins

I truly suspect the issue lies in the Singal Return or Ground path as being the most likely.

This is just me - Brainstorming and thought about the PCM grounds, more so the G117 and the PCM connectors were disturbed during engine removal - the contacts can easily be pushed in or damaged

Hopefully - you can get it isolated

As one of his codes is:
P06A8 - Sensor Reference Voltage C Circuit Range/Performance

Description:
This DTC sets when the VREF circuit is not within a calibrated voltage range.

Possible Causes:

• VREF circuit short to voltage
• VREF circuit short to ground
• Damaged sensor

I would lean towards a pinched cable shorting VREF short to ground or a bad sensor.

 

[airline tech]

Which is why - we need to check each side of the circuit - VREF & Signal Return
To isolate is it a bad VREF or Bad Ground

Noting that the Exhaust Pressure = Circuit High, this may point to a bad ground floating the signal wire (high)

Noting that we have 3 -lost com codes - (is this a lost VREF?) - possible

Noting we have a - Throttle Position code and a lost com code

Noting that - we have separate VREF (Circuits) output from the PCM and separate signal returns feeding into the PCM - HOWEVER since the manuals do not show the internals (like the voltage regulator) that's dropping the voltage to 5-Volts - makes it difficult to know what each voltage regulator is feeding - how many pins and what (specifically)

Yes, there are a couple way to actually MAP the circuits.
1. PCM (removed) Pin to Pin (Internally Bussed)
2. Create a - Short to Ground and note with the PIDs - what dropped to (0) for the sensors

Noting that - The Cooling Fan Motor - is on this circuit (Known Issues) with the harness and also this engine had coolant intrusion that may have shorted a sensor

So, for the Lost Com codes - it could be a VREF short to ground and the Ex Press Sensor (Circuit High) could be a signal return issue - It depends on which one to tackle first and which direction to go - it boils down to the most important (and that is the results) of the first set of checks I posted - VREF or Signal Ground

 

[diesel924]

Boy do I wish I had this truck in my shop. This set of codes looks very interesting. I have Forscan but I never really use it, all my troubleshooting is done with IDS/FDRS. If I had it in my shop, I would erase the codes (after noting them) and do a key-off-engine-off test. Hopefully Forscan has this. The codes that immediately come in I would troubleshoot.

I'm as guilty as the next guy of doing this: I have several codes and I look for what grd/pwr all those components have in common. HOWEVER, since a blind monkey put this truck back together, there very well be more than 1 disconnected/shorted wire! If you look for parallels you might be chasing your tail for quite a while. Pick the top code and troubleshoot that first.

Back probing....oh boy. I've seen very good mechanics mess up terminals by back probing. Usually it's by sliding the correct(ish) probe between the wire seal and the wire, towards the pin crimp and looking at the DVOM or scope and not seeing anything happen....so they push further. Now a problem has been created OR even worse, an intermittent has been created. Be careful!

 

[silversurfer]

got it running smooth after I hired a mechanic. He solved in 1 hour what Caruso Ford could/would not in 3 months. I still have to replace the shorted fan clutch (got one coming from eBay for $250 instead of $750 from dealer). I’m gonna try to return/resell the $150 salvage pcm I had installed as my original pcm was fine (good thing I didn’t pay Caruso $3k to install new pcm like they wanted). I’m just waiting on the guy to come back and re-run the immo reset on my old pcm which I swapped back and I’m good to go.

*edit - I also need to buy a new battery since Caruso fried mine somehow. And I might buy another engine cover because Caruso threw mine away.

 

[diesel924]

Small claims court seems to be a good option at this point.

 

[airline tech]

got it running smooth after I hired a mechanic. He solved in 1 hour what Caruso Ford could/would not in 3 months. I still have to replace the shorted fan clutch (got one coming from eBay for $250 instead of $750 from dealer). I’m gonna try to return/resell the $150 salvage pcm I had installed as my original pcm was fine (good thing I didn’t pay Caruso $3k to install new pcm like they wanted). I’m just waiting on the guy to come back and re-run the immo reset on my old pcm which I swapped back and I’m good to go.

*edit - I also need to buy a new battery since Caruso fried mine somehow. And I might buy another engine cover because Caruso threw mine away.

That is Great news:

As I suspected - Outside the box - thinking - Signal Return issue @ G117.
This could cause the Crank Sensor (Signal) wire to have been overheated (giving) a stretched appearance.

The Cooling Fan - Wire Rubbing and or Damage only enhanced the issues due to the bad ground

Now the question is: Regarding Cooling Fan Harness Damage

Was this damage present before the engine change?
Was the support hose degraded and not fully addressed during engine change?
Was the support hose ever reconnected prior to engine start (new engine)?

Causing the wire damage at the Cooling Fan

So, Replace the Cooling Fan Clutch and FULLY inspect and or repair the wires for damage and perform the FOB and PATS - Programming and you should be good to go.

On a side note - It may just be the wire rubbing issue causing the - Cooling Fan issues but since this has had numerous issues it may be a good idea to just replace it - as long as the wiring is fully inspected for any damage.

Glad to hear the issue was resolved

 

[silversurfer]

That is Great news:

As I suspected - Outside the box - thinking - Signal Return issue @ G117.
This could cause the Crank Sensor (Signal) wire to have been overheated (giving) a stretched appearance.

The Cooling Fan - Wire Rubbing and or Damage only enhanced the issues due to the bad ground

Now the question is: Regarding Cooling Fan Harness Damage

Was this damage present before the engine change?
Was the support hose degraded and not fully addressed during engine change?
Was the support hose ever reconnected prior to engine start (new engine)?

Causing the wire damage at the Cooling Fan

So, Replace the Cooling Fan Clutch and FULLY inspect and or repair the wires for damage and perform the FOB and PATS - Programming and you should be good to go.

On a side note - It may just be the wire rubbing issue causing the - Cooling Fan issues but since this has had numerous issues it may be a good idea to just replace it - as long as the wiring is fully inspected for any damage.

Glad to hear the issue was resolved

It's highly likely imo this damage was caused by the dealer during engine installation. I know for certain that they thrashed a lot of other stuff during installation like the 2 wire harnesses belonging to my lightbar which were ripped off of their connection points on the battery by them:

This definitely wasn't like this when I brought the truck in. First thing I did when I pulled over is disconnect the battery and reconnect. I inspected all of this stuff and it was all in tact.

The way I discovered this stuff was after engine installation the dealer contacted me that the acc module was missing... so I told them it's not missing, it's relocated a foot higher up from it's standard location. They still couldn't/wouldn't find it even after I sent them actual photos of it's location but they found the disconnected wire connector for it. I come into the dealer and see this connector dangling down underneath the vehicle and I plug it back in for them... that's when I look up top in the engine bay and see the lightbar harnesses thrashed.

It seems to me that if they caused all this damage (and the other engine wiring issues) it's plausible that they bumped the exposed fan as well... I've never seen alerts for the fan in the past.

Anyways, thanks again for all of this diagnostic info @airline tech @RangerBill @diesel924 and others. I'm not a mechanic and it all seemed like such a mess I just decided to hire someone. I am going to pursue small claims route soon here... I just keep finding new stuff that they screwed up or left incomplete... I went to put the skid plate back on last night (they gave me truck with it off) and there is no hardware for it... I'm still trying to figure out how to attach that diff breather to the new motor in the correct spot... need proper bolt for that too.

But truck is running smooth now and only throwing the one code of the disconnected fan. Should be fine to drive around in the meantime without that connected right? It seems that the fan defaults to high speed in this case?

 

[airline tech]

These may provide a better visual (guidance) for the Breather Tube

Lower Bracket (Clamp)

Upper Bracket - note routing

and this is viewed from the driver's side wheel well - same access as the oil filter

 

[silversurfer]

These may provide a better visual (guidance) for the Breather Tube

Lower Bracket (Clamp)

Upper Bracket - note routing

and this is viewed from the driver's side wheel well - same access as the oil filter

I was able to access and attach easily through the side in the wheel well. Thanks for the images!

man, I’ve also discovered that all the clips they removed they didn’t put back . I had to get a pack of push clips and replace 5 of them along with the 5 missing bolts!

 

[silversurfer]

I just discovered another major WTF while going through my truck glove box. My 4 lug locks in the pouch where the lug lock key socket is kept. I check the wheels and all are missing the lug lock lugs. I’ve removed everything from the inside of the truck and no lug key to be found anywhere…. Insane.

If anyone is ever thinking about getting service done at Caruso ford in Long Beach California and stumbles across this post, I recommend you go elsewhere. Extreme incompetence and outright hostility and lying when you call them on it. FYI.

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