PCS Pressure Control Selenoid short circuit

[epenny]

Hi, anybody knows what the 'Pressure Control Selenoid' is' I get a P1749 error on the scanner, MIL is on and sometimes I can't engage D or R. Thanks.

 

[xxblackxx]

Electronic Pressure Control (EPC) Solenoid

The electronic pressure control (EPC) solenoid is a variable force style (VFS) solenoid. The VFS type solenoid is an electro-hydraulic actuator combining a solenoid and a regulating valve.
The powertrain control module (PCM) varies the current to the EPC solenoid.
This action causes the solenoid to regulate transmission line pressure and line modulator pressure. This is done by producing resisting forces to the main regulator and line modulator circuits. These two solenoids control clutch application pressures.
Symptoms:

Electronic pressure control (EPC) shorted to ground or failed low may result in a false VSS DTC. Diagnose EPC concerns first, then recheck VSS.
Maximum EPC — high pressure resulting in harsh engagements and shifts.
Zero EPC — low pressure resulting in no 3rd and 5th gear, slips in 2nd and 4th with high input torque. Alternate firing of engine to limit torque.
DTCs: P1746*, P1747*

* Output circuit check, generated by electrical conditions.

 

[epenny]

Yeeeeees!!!!

That exactly whats happening! Somethimes I just can't get on Reverse! Or if the engine was at stop I can't move. the gears won't engage. So it's call EPC.... You were right I rechecked the scanner and its P1747. Where is that module? Simple thing to change or Ford hands to take?

Thanks a lot!

By the way, do you know where the CD Changer connector is? I can't find it.

 

[xxblackxx]

If you're truck were to have a CD Changer, it looks like it would have been located in your center console..

The connector seems to come in from the front of the vehicle side of said center console and goes through the aluminum mounting bracket and into the changer.

hope that helps, if you need pics, ill host them up for you.

 

[xxblackxx]

Oh yeah, the EPC is inside the trans, so you'd have to drop the pan to get at it. Not sure if you are that mechanically inclined, as if you mess something up, you'd be fubar.

 

[epenny]

Thank you so much, I 've done this before in my '94, so with Autozone and some luck I went to my local store and bought the filter and atf. I get all bolts out and.... The pan wount get out! There is a smll difference, in the 97 there is a muffler just under it. So there is no space betwen the front transmission, the pan and the muffler to get it off.

It's gona be a loooong weekend



Ernie

PD, there is no connection in the center console, that came in 98. Its supose to be at the back somewere.

 

[epenny]

Reading was short, there was another thread of folk installing an auw filter because the front driveshaft needs to be removed in order to get down the pan. Four bolts and the front driveshaft and the pan were out.

Now, ¿which one of the solenoids is messing with mwe?

Thanks again, this site rocks!

 

[xxblackxx]

Removal

Disconnect battery ground cable.

WARNING: THE ELECTRICAL POWER SUPPLY TO THE AIR SUSPENSION SYSTEM MUST BE SHUT OFF PRIOR TO HOISTING, JACKING OR TOWING AN AIR SUSPENSION VEHICLE. THIS CAN BE ACCOMPLISHED BY TURNING OFF THE AIR SUSPENSION SWITCH LOCATED IN THE REAR JACK STORAGE AREA. FAILURE TO DO SO MAY RESULT IN UNEXPECTED INFLATION OR DEFLATION OF THE AIR SPRINGS WHICH MAY RESULT IN SHIFTING OF THE VEHICLE DURING THESE OPERATIONS.

Raise and support the vehicle.
Drain the transmission fluid. Refer to the procedure in this section.
Remove the transmission fluid filter.
Remove the transmission fluid filter bolt.
Remove the transmission fluid filter.

NOTE: Main control assembly does not need to be removed for solenoid service.

Remove wire loom guide and protector.
Carefully lift up on wire loom guide and protector and disengage the retaining pins from the solenoid clamps.

Disconnect the appropriate solenoid electrical connector.
Disconnect shift solenoids electrical connectors.
Disconnect the torque converter clutch (TCC) solenoid electrical connector.
Disconnect the electronic pressure control (EPC) solenoid electrical connector.

CAUTION: The TCC solenoid and converter modulator valve may pop out of its bore. This may damage the solenoid or converter modulator valve.

CAUTION: Shift solenoid (SS3) may pop out of its bore. This may damage the solenoid.

Remove the shift solenoids (7G484).
Remove the wire harness.
Remove the solenoid clamp bolts.
Remove the solenoid clamp.
Remove the appropriate solenoid(s).


Installation

Install the new solenoid(s).

CAUTION: The solenoid clamp must be installed in the TCC and EPC solenoid grooves, shift solenoid pockets and the No. 204 plug.

Install the solenoid clamp.
Position the solenoid clamp on the main control valve body.
Install the solenoid clamp bolts.

Connect the six solenoid electrical connectors.
Connect shift solenoid SS1, SS2, SS3, SS4 electrical connectors.
Connect the torque converter clutch (TCC) solenoid electrical connector.
Connect the electrical pressure control (EPC) solenoid electrical connector.

CAUTION: Excessive pressure may break the retaining pins.

Install the main control valve body wire loom.
Align the retaining pins to the holes in the solenoid clamps and gently press in the main control valve body wire loom guide and protector.

Install the transmission fluid filter.
Install the transmission fluid filter.
Install the transmission fluid filter bolt.

Install the transmission fluid pan.
Position a new transmission fluid pan gasket on the transmission fluid pan.
Align and install the transmission fluid pan.
Loosely install the 18 transmission fluid pan bolts.

Tighten the transmission fluid pan bolts.

NOTE: If equipped with air suspension, reactivate the system by turning on the air suspension switch.

Lower the vehicle.
Connect battery ground cable.

Fill the transmission to the proper fluid level and check for proper transmission operation.
Use MERCON V® Automatic Transmission Fluid meeting Ford specification XT-5-QM.

#3 is the EPC solenoid


Id assume the CD changer connector would be in the right rear quarterpanel plastic, but dont quote me on that. The 97 ford service manual claimed it was in the center console.. hah, what do you know, wrong again!

lol!

 

[epenny]

xxblackxx,

thank for this, I 've done it and fount all solenoids but the EPC working. Do you know the part number for that?

Thanks for the tip on the CD Changer, next weekend I'll take a look.

________

Ê

 

[xxblackxx]

sorry, not sure on the part # for it, and I couldnt find it on fordpartsnetwork.com....

might want to check your local dealer for that.

 

[glfredrick]

Mine was acting the same way - but I also did a full rebuild. The front planetary was toast (along with the bands - clutches and seals). I replaced the EPC, both regular bands (not the low reverse) and all the clutches and seals. Now, it still will not go into D or R (1 & 2 work fine). Any ideas from you guys out there that do this often?

I am wondering if it is one of the other solenoids. I did some reading today on the gears site and they recommend a solenid replecement when phyisical damage happens insde the trans. I am hoping not to have to pull the entire unit off the truck!

BTW, the front driveshaft does have to come off to remove the pan when there are two converters. I also added an oil drain plug to make the task easier next time! (B&M sells them - at any parts store).

 

[epenny]

This is a mess. I change belts, clutches ands seals, and filter, and oil, and EMC, and TC...........

Still wount work in D or R sometimes. Actually it happens wen worm, so I add another cooler for the transmission fluid and Prolong for Auto Trans.

So now when its not to hot, and I don't use de Air conditioner it doesn't boder.

Ë.-

 

[Opera House]

EPC

There was a TB on the bracket that held the EPC solenoid cracking. There is an improved solenoid that may not work with the old bracket or requires the new bracket. So, be sure to ask enough questions when you order the part. Check the valve body bolts. If lose you may need new VB gaskets. That may need a new improved seperator plate. Luckily I bought a spare tranny so I can swap parts at will. I paid for the tranny about the same price as the EPC. It had 52K with a blown VB gasket.

 

[epenny]

Opera House,

thats a good idea, I'll look for the bracket. The new EPC and new TC are indeed diferent. Claps and bodies of the solenoids are bigger and stronger, so maybe the bracket is not solid enough.

Thank you.

EPC

 

[fndwl]

overdrive light blinking

Hi, This is not the same problem as you are discussing but I recently had my transmission rebuilt at a shop. I have a 95 limited 4x4. The tranny works fine except the overdrive light keeps blinking. I have taken it back 3 times and they suposedly have fixed it but haven't. This last time I had it 2 hours before it started blinking again.
It is going into overdrive and out of overdrive when I press the button so I know that is working. I know it is saying something is wrong but don't know what code is comming up when they test it. The last time I had it in they said they replaced the wiring loom? Please help!!!