Greetings All,

Just had the Gearbox Fault message pop up yesterday morning on my '02 V6. Never had that before. Car still seemed to drive fine.

My code reader showed P0745. That translates to "Pressure control solenoid 1 stuck" per this guide, courtesy of Gus:

http://www.jagrepair.com/images/Auto...os/PE20001.PDF


I was able to clear the fault, but on the drive home it returned once as pending.

Not much in the forum for this code. One of the FAQ's had a little bit about it, but unfortunately it's almost worthless now that the pics are gone:

https://www.jaguarforums.com/forum/s...ighlight=p0745


Any thoughts? Could it somehow be related to low fluid? The poor transmission (5-speed) is overdue for a service anyway. I'm wondering if low pressure due to low fluid could have misled the computer into setting this code, but maybe I'm just grasping at straws. I've already got everything I need to drop the pan, replace the filter, etc. I'd just hate to have to go back in if this needs a bona fide repair, versus just rolling the dice on the proper quantity of fresh fluid.

 

Check the fluid level first and top up as needed. If the solenoid is indeed stuck, it may be best to exchange it for a new or remanufactured one:

https://www.ebay.com/itm/5r55n-Solen...-/361501687427

 

What are your thoughts on draining and refilling the transmission, with a fresh filter? Normally I'm a big advocate of "As little as possible for as long as it takes". However, as much work as it is to get the car up on 4 jackstands, and then I'm still going to get slimed anyway just topping off the fluid, it feels like I may as well spend the extra 20 minutes to drop the pan and replace the filter...

 

Well Karl i say the more you have to do to get the car positioned to work on ...the more work i like to get done..my 2 cents is do the tranny service..i am no pro just a guy that hates to say....damn i should have done that

 

If you must work on the car on stands, then it may indeed be best to just change the fluid and pan/filter at the same time. If you have access to a lift/hoist, then top off the fluid first.

 

New (reman) part is in hand, as suggested:




The big question: Is there supposed to be a gasket where the solenoid pack will bolt up to the rest of the transmission? Per this exploded view, I'm not seeing one, but I'd like to be positive ahead of time.




Solenoid pack (#160) circled in red

 

The solenoid pack bolts directly to the plates for the rest of the valve body.

Check the sump pan and solenoid pack passages and solenoids for metallic flakes, which could indicated another part failure is occurring and contamination has caused the solenoid pack to fail.

 

Got the solenoid pack swapped out. Not a lot of fun, but nothing too difficult. The whole process wasn't much worse than changing the transmission filter and refilling. So far, so good, but I'd like to put some more miles on the car to be positive, as the fault didn't appear on every trip. Inside of the pan was surprisingly clean, with barely any debris and only the tiniest bit of fuzz on the magnet.

One little gotcha:

The solenoid pack has a connector on the top, with a bolt from above. Access is kinda poor. You will need a 10mm ratcheting box end wrench. There wasn't enough room for a socket.

Here's the solenoid pack. The connector sticks up and passes through a hole (approx 1" diameter) in the oil pan flange on the US driver's side, near the front. Note the bolt hole in the middle of the connector:





Here's a screenshot stolen from a Youtube video, with an arrow added pointing to the location of the connector. The connector is part of the vehicle harness, so it stays with the car when the transmission is removed:





Here's a bottom view of the connector, showing the captive bolt in the middle:






More pictures of the connector here:

https://www.cascadetransmissionparts...repairkit.aspx


You'll be working by Braille to unthread this bolt. You can't really see it, so there's no way to get a good picture of it installed. The bolt is captive, so be careful when loosening it as it will tend to lift up the connector. Be careful the connector doesn't lift up completely and let dirt into the transmission.

Also, one of the solenoid pack bolts is semi-hidden at the front edge. The Torx bit I have is short with a wide body, and couldn't get in there straight. A long narrow bit would have worked a lot better.

 

Glad to see you didn't find much metal debris in the pan. Another common problem with the 5R55N/E/S/W is wear in the servo bores causing band application to be inconsistent leading to premature failure of the overdrive and intermediate bands.

Servo bore wear can also cause DTCs to be set indicating failure of the solenoids, so hopefully this isn't the case with your gearbox.

 

Typing very quietly so my car doesn't hear me, but I think I'm going to call this one good. I've driven the car nearly every day since replacing the solenoid pack over three weeks ago. The fault has not returned.

Many thanks to NBCat for the repair advice.