DIY: Replacing Transmission Pressure Switches

[NJGuy]

DIY: Replacing Transmission Pressure Switches

I recently had to change out one of my transmission pressure switches on my 2005 Pilot, so I decided to take a few photos while doing it and share them who might have to perform the same procedure in the future.
For those of you who are interested in the story behind this, please see the following thread: Sporadic vibration at low speeds

This procedure has been posted by others on different Honda and Acura vehicle forums, and the threads on those forums provide some insight as to why it was important that the pressure switches were changed.
I'm posting this thread in the "Maintenance" section of the forum since most DIY threads are here; also, many Acura TL owners have or plan on changing their transmission pressure switches as another maintenance item. If the moderators feel that there is a more appropriate place for this thread, they can feel free to move it.

Purchased parts:
(1) 28600-RAY-003
(1) 28610-RAY-003
(2) 90471-PW7-A00 (Washer/Gasket)
(5) 91501-S04-003 (Fender Clips; I broke 3 and bought 2 extra)

Tools needed:
Floor Jack & Jack Stands (or vehicle lift)
22 mm wrench or deep socket (for pressure switches)
10 mm wrench or socket
Small flathead screwdriver (or clip removal tool if you have one)
Torque wrench

Step 1
Break the lug nuts loose on the driver side front wheel. Raise the front of the vehicle (of course, remember to exercise all safety precautions and use common sense when doing this). I adjusted my jack stands so that the driver side sat a bit higher than the passenger side. I did this to minimize the amount of ATF that might spill from the transmission. Remove driver side front wheel.

[NJGuy]

Step 2
Using the small flathead screwdriver (or clip removal tool), remove the fender liner clips from at least the halfway point of the wheel well and forward towards the front bumper (probably between 8 and 10 clips). Move the fender liner and front lower splash shield aside.

[NJGuy]

Step 3
The third gear pressure switch is located behind the black bracket. Using the 10 mm wrench, remove the upper and lower bolts that mount the black bracket to the transmission case. Rotate the bracket away from the transmission to reveal the third gear pressure switch.

[NJGuy]

Step 4
Unclip the connector to the pressure switch by pushing on the wire connector's tab and pulling the connector away from the switch. Using the 22 mm wrench, loosen and remove the third gear pressure switch.

[NJGuy]

Step 5
Install the new washer/gasket on the new third gear pressure switch. Install the third gear pressure switch onto the transmission and torque to 14 ft-lbs. If you have any dielectric grease, it probably isn't a bad idea to put some on the connector. My connectors were clean and I didn't bother.
Remove the clear protective boot on the pressure switch. Reconnect the wire to the third gear pressure switch, ensuring that the tab clicks into place. Reinstall the black bracket and 10 mm bolts.

[NJGuy]

Step 6
The fourth gear pressure switch is easier to access because it is uncovered. Unclip the wire connector from the fourth gear pressure switch. Loosen and remove the pressure switch using the 22 mm wrench. Install the new washer/gasket on the new pressure switch; install the pressure switch onto the transmission and torque to 14 ft-lbs. Remove the protective boot and reconnect the wire.

[NJGuy]

Step 7
Reinstall the front lower splash shield and inner fender liner. Reinstall the driver side front wheel. Lower the vehicle onto the floor and torque the lug nuts to 80 ft-lbs. Test drive vehicle to ensure that there are no major shifting issues or transmission error codes.


I know that this DIY thread isn't perfect; I didn't take pictures of every individual step and some of the photos don't exactly match up. Also, like every other DIY thread, I give the following disclaimers: "do this at your own risk"; "I take no responsibility in any damage this may cause to your vehicle"; "I take no responsibility for any injury that may occur"; "positive results are not guaranteed"; etc., etc. (did I leave any out?)

Also, I am willing to make any changes or corrections to my posts regarding this procedure. I am also willing to answer any questions that anyone may have.

[N_Jay]

Originally Posted by NJGuy

Purchased parts:
(1) 28600-RAY-003
(1) 28610-RAY-003
(2) 90471-PW7-A00 (Washer/Gasket)
(5) 91501-S04-003 (Fender Clips; I broke 3 and bought 2 extra)

Where did you get those part numbers?
They seem to be for a later year (although could be functionally compatible with our year)

'03 shows
28600-P7W-003
AND
28600-P7Z-003

[N_Jay]

Oh, And thanks for the pictures.

Will be attacking it tomorrow.

[NJGuy]

Originally Posted by N_Jay

Where did you get those part numbers?
They seem to be for a later year (although could be functionally compatible with our year)

'03 shows
28600-P7W-003
AND
28600-P7Z-003

Those part numbers I listed are for an '05. They are the ones the dealership gave me; I also went to the Bernardi Honda website, entered my VIN, and confirmed the part numbers there to make sure they gave me the right ones. I didn't check whether or not the parts are different for any other model years. I also have a feeling that on some model years, the pressure switches may be in locations that are different than mine; though I didn't check that either.
Oh, by the way, I almost mixed up the two pressure switches when installing them. I'd recommend that you double check which one goes where when doing the replacement.

If you ordered the parts from Tim (Honda Acura Planet), I'm sure he picked the right ones for you. That is, if you trust him.

[N_Jay]

Yes, "05 is the first of the new transmission.

I wonder if the pressure specification changed or if the electrical connector changed.

These things are not much more then calibrated oil pressure switches.
$50 for an oil pressure switch is freaking ridiculous, but what choice do we have.

Hmm, get a typical analog sender, then feed that into an A/D, and into a PIC processor, then we can watch the pressure and calibrate the output?

[NJGuy]

Originally Posted by N_Jay

Oh, And thanks for the pictures.

Will be attacking it tomorrow.

No problem. This forum has already shown me how to do many things on my Pilot and has given me a wealth of information. So I felt at least some obligation to try to give back a little. The pictures are there for anyone who can benefit.

Hopefully the replacement solves your issues. I figure you'd be the one of the few here who could give a real accurate report of the results. Let us know how it goes.

[humanoid]

Thanks for the write-up, saved for future reference! Nice job!

[rocky]

Nice job. This should be stickied.

Can't recall if this was preventative maintenance on your part or you were having a driveablility issue.

Be interested in hearing back from you in a few days after you've put some miles on your Pilot.

[cofetym]

Nice,Very Nice.