I have searched the site for code p0478, but cant find the answer to my question. I plugged my programmer up the other day and ran the diagnotics test on it and pulled code p0478 (which read Exhaust Pressure Control Valve High Input). I read that you might have to pull it out and clean but knowbody states where exactly it is. There was the SES light that came on. I was pulling the camper a few days before I ran the test and the Engine temp guage went to hot when pulling up a grade. Does anybody know a fix to this code or know the location of where this control valve is at. Thanks.

 

The EBP sensor is on the drivers front corner of the engine mounted on a small bracket and has a small tube that runs to the exhaust manifold. I don't think it would cause you to run hot, but it might if it gives an incorrect reading to the PCM causing incorrect turbo boost. Do you have any coolant loss and have you checked to see if your radiator might be obstructed (grass, bugs, etc). Are you running a programmer/tuner/chip or do you just have a diagnostic tool?

 

The 6.0 troubleshooting guide has this to say about your error code:
<table border="1" cellpadding="3" cellspacing="0"><tbody><tr><td align="center" valign="top">P0478</td> <td align="left" valign="top">Exhaust Pressure Control Valve High Input</td> <td colspan="3" align="center" valign="top">Update the calibration. Check for other DTCs and diagnose those first.</td></tr></tbody></table>So do you have any other codes??
_______________________________________________
<table cellspacing="0" width="95%"> <tbody> <tr> <td> KA: Turbo Charger System Performance
Introduction
</td> <td align="right" width="25%">
</td></tr></tbody></table> <hr> Signal Functions The variable geometry turbocharger (VGT) is controlled by the powertrain control module (PCM). The PCM utilizes an exhaust pressure inference from the MAF sensor to calculate exhaust pressure and adjust the VGT solenoid duty cycle. The VGT solenoid receives a pulse width modulated (PWM) signal from the PCM that controls the solenoid on/off time. The VGT solenoid directs oil to a piston within the actuator housing. The direction of oil flow to the piston increases or decreases the exhaust pressure.


Sensor Bias The VGT solenoid control is based on input sensors. The input sensors are used to calculate engine speed, desired fuel quantity, altitude, and exhaust pressure. The amount of voltage the sensor deviates from a calculated reference value (sensor bias) may cause a commanded versus actual pressure calculation error.


Detection/Management The PCM monitors the exhaust pressure. A DTC is set when the difference between the commanded and the actual exhaust pressure is not within the calibrated limits.


CAUTION: The powertrain control module (PCM) harness connectors must be properly seated and the connector latch properly attached to eliminate possible driveability concerns or a no-start condition. Installing PCM connectors on an angle may cause an improper connection, misdiagnosis, and damaged components. Install the connector until the lever pivots and seats itself. Apply light pressure to get the connector into position on the PCM and then fully seat the connector.

Note: After removing the connectors, always check for damaged terminals and pins, connector corrosion and loose fitting terminals.

Note: When the PCM engine harness connector is disconnected, additional DTCs will be set. All DTCs must be cleared before returning the vehicle to service.

DTC Descriptions

• P0478 = Exhaust Pressure Control Valve High Input
• P2262 = Turbo/Super Charger Boost Pressure Not Detected
• P2263 = Turbo/Super Charger System Boost Performance

 

ozx3+1 - No this was the only code that showed up.

 

In reference to npccpartsman post below, Are you running a programmer/tuner/chip or do you just have a diagnostic tool? It's a very important question...

 

Yes. I am running a Superchips Flashpaq programmer.

 

And the reported issue occurred while programed? If so, were you running a hot tune? did you try to roll-back to stock and then try to duplicate the heat-wash? Also, doesn't the flashPaq have logging? if it does, you can do some data comparisons... By the way, my SCMT1704A (predecessor to the FlashPaq) reads code on my 03 that aren't really there. I had a scare with codes that I read with the 1704, but a Ford diagnostics tool (palm pilot on steroids) read NO CODES. It could happen.

Oh yeah... "SES light"? Mi no hablo "SES"... Acronym definition required, please

 

SES==service engine soon==CEL. I had to think about it myself.

ok--reprogram to stock, reload tune and see if you still have issues. I've had some crazy ones lately (2614) that I can't find anywhere, but have no issues with my truck.

Have you had your truck reflashed lately or have you recently updated your tuner?

 

AH! Well that makes good sense...

As for the P2614, I found this... I only have the info on the 03's
<table width="95%"> <tbody> <tr> <td> 2003 PCED On Board Diagnostics 6.0L Diesel
</td> <td align="right"> SECTION 5: Pinpoint Tests
</td></tr> <tr> <td>
</td> <td align="right"> Procedure revision date: 05/24/2004
</td></tr></tbody></table> <hr> <table cellspacing="0" width="95%"> <tbody> <tr> <td> AT: FICM Circuit Fuel Delivery Error
</td> <td align="right" width="25%">
</td></tr></tbody></table>
<hr> AT1 PRELIMINARY DIAGNOSIS FOR DTC P2552

• Connect the scan tool.
• Retrieve and record all engine and transmission continuous DTCs.
• If DTCs P2614 or P2617 are present, follow DTC diagnostic for P2552.

Is DTC P2552 present?
<table border="1" cellpadding="3" cellspacing="0" width="92%"> <tbody> <tr> <th width="50%">Yes </th> <th width="50%">No </th></tr> <tr> <td width="50%">For DTCs P1378 or P1379, GO to Pinpoint Test S .

For DTC P2552, GO to AT2 .

For DTC P0148, GO to AT5 . </td> <td width="50%">CLEAR DTCs and RETEST the system. If other DTCs appear, GO to the appropriate pinpoint test for diagnostics. </td></tr></tbody></table> AT2 DIAGNOSTIC TROUBLE CODE (DTC) P2552

• Note: Refer to the PCM and component connector pin numbers at the beginning of this pinpoint test.
• Possible causes:
  • FICMM line open
  • FICMM line shorted to ground
• Key off.
• Disconnect the FICM electrical harness connector C.
• Key on.
• Measure the voltage between FICM harness connector C pin 9 and ground.

Is the voltage greater than 10.5 volts?
<table border="1" cellpadding="3" cellspacing="0" width="92%"> <tbody> <tr> <th width="50%">Yes </th> <th width="50%">No </th></tr> <tr> <td width="50%">RESTORE the vehicle. CLEAR all engine and transmission DTCs. RETEST the vehicle. If DTC P2552 returns, REPLACE the FICM. If no DTCs are present, return the vehicle to service. </td> <td width="50%">GO to AT3 . </td></tr></tbody></table> AT3 CHECK FICMM CIRCUIT FOR A SHORT TO GROUND

• Key off.
• Disconnect the PCM engine harness electrical connector.
• Measure the resistance between PCM engine harness connector pin 28 and ground.

Is the resistance greater than 10,000 ohms?
<table border="1" cellpadding="3" cellspacing="0" width="92%"> <tbody> <tr> <th width="50%">Yes </th> <th width="50%">No </th></tr> <tr> <td width="50%">GO to AT4 . </td> <td width="50%">REPAIR short in FICMM circuit. RESTORE the vehicle. CLEAR all engine and transmission DTCs and RETEST the system. </td></tr></tbody></table> AT4 CHECK FICMM CIRCUIT FOR AN OPEN

• Measure the resistance between PCM engine harness connector pin 28 and FICMM connector pin 9.

Is the resistance less than 5 ohms?
<table border="1" cellpadding="3" cellspacing="0" width="92%"> <tbody> <tr> <th width="50%">Yes </th> <th width="50%">No </th></tr> <tr> <td width="50%">RESTORE the vehicle. CLEAR all engine and transmission DTCs and RETEST the system.

If DTC P2552 returns, REPLACE the PCM. CLEAR all DTCs and RETEST the system. </td> <td width="50%">REPAIR open in FICMM circuit. RESTORE the vehicle. CLEAR all engine and transmission DTCs and RETEST the system. </td></tr></tbody></table> AT5 DIAGNOSTIC TROUBLE CODE (DTC) P0148

• Connect the scan tool.
• Retrieve and record all engine and transmission DTCs.

Is DTC P0148 present?
<table border="1" cellpadding="3" cellspacing="0" width="92%"> <tbody> <tr> <th width="50%">Yes </th> <th width="50%">No </th></tr> <tr> <td width="50%">REFER to the performance worksheet in Section 4 .

PERFORM drive cycle.

Reflash PCM. If DTC P0148 returns, REPLACE the PCM. </td> <td width="50%">CLEAR DTCs and RETURN the vehicle to service. </td></tr></tbody></table>



<hr>

 

Thanks Oz. It's the only code that showed up. I keep getting "trash" codes for some reason. Clear them and they never come back, always something different. Maybe I should make a list and see if they point at one thing specific. I really wonder if it wasn't from a bad starter causing electrical issues. I'll keep looking and logging.

I will run these tests to see if I have another problem. I'm also suspecting a wiring harness problem too, as most of my codes have all been voltage related.

 

DTC roulette! Fun... I wonder what the code for "random trash code" is??