'03-'06 MDX - 3rd & 4th Gear Transmission Switches / Sensors DIY by Majofo

10 minute read

'03-'06 MDX - 3rd & 4th Gear Transmission Switches / Sensors DIY 

Compliments of Majofo @ http://acurazine.com

10-7-2009

I have an '03 X ~110k and my trans has been slipping & shuddering in 1st (unrelated) but I also noticed slipping in the 3rd upshift as well. I have also been plagued by harsh downshifts & jerky upshifts. I decided to change out the transmission switches / sensors in an effort to alleviate some of my issues. (btw.. I don't have AT DTC's). The result has been smooth downshifts & upshifts. My 3rd gear is much smoother and shifts firmly without slipping / revving. My 1st gear is still slipping but I knew the swap wasn't going to cure it. This DIY is good preventative maintenance to slowly failing pressure sensors going out-of-spec and not maintaining appropriate line pressure. 

Highs

Easy - 1.5 hrs, < $100

Lows

None unless spending $100 is too much for your budget.

Tools

• Socket set - 10mm, 12mm, 14mm?, 22mm (deep neck)
• Flathead Screwdriver
• Pliers
• Shop towels

Parts

• 3rd Gear Pressure Switch / Sensor 28610-RAY-003 #13 ~$33
• 4th Gear Pressure Switch / Sensor 28600-RAY-003 #12 ~$33
• 2 x Pressure Switch / Sensor washers / gaskets 90471-PW7-A00 #17 (optional) ~$2 each
• Extra splash guard tabs 91503-SZ5-003 & 91501-S04-003 (recommended) ~$1-2 each
• ATF (recommended) - price depends on what you use, I recommend Z1 w/ accelerated change intervals.

^ acuraoemparts

2001-02 MDX Owners

Btw.. if you own a 2001-02 MDX and you want to change out the pressure switches / sensors as well you have it much easier. Your transmissions were adopted by the 3G TL (2004-06) which there's already a DIY. On a related note, the 03-06 MDX transmission was adopted by the 07-08 TL with some tweaking including the addition of a pressure switch for the 4th gear. The Aziner (sixsixfour) who created the TL DIY thread put in the incorrect (yet correctly spec'd / same spec) switches, the P/N's he used to do the swap are the actual P/N's to the 01-02 MDX AT's. You can probably use the same ones used in this DIY as well. The only difference is the body of the switch / sensor is stepped while the other is flat.

http://tl.acurazine.com/forums/showthread.php?t=729149 <--- Click Link

Step 1: Strip it down

Unfortunately for us, we need to remove the intake tube, which is why I recommend doing an ATF drain & fill. I did a drain & fill before the swap so I don't have pics of it included. Anyways, take off the engine cover to get to the intake tube. When you remove the intake pipe, unbolt the filter housing first to give you some room to maneuver. Loosen the throttle body clamp, then use pliers / channel locks to remove the spring clamp on the header intake pipe / breather and slide it back. You should now be able to flex the intake pipe off and push it back from the filter housing & throttle body.  

The service manual says you need to remove the battery, battery tray & pan to get to the 4th gear pressure switch but it's not necessary. I removed them but you can save yourself some time by skipping that step.

Step 2: Remove 4th Gear Pressure Switch / Sensor

The service manual says you need to remove the shift cable which is why you are required to remove the battery tray. Unless you're going to adjust the cable, it's unnecessary. You only have to loosen the top bolt of the wire harness bracket in order to get access to the 4th gear pressure sensor. 

Unplug the connector first by pushing in the clip and then unbolt the top bolt (marked in blue) on the wire harness which pushes against the pressure sensor / switch. You should now be able to slide your 22mm deep neck socket over the pressure sensor. Remove it and then carefully clean off the area while avoiding contaminating the inlet before installing the new pressure sensor & washer / gasket. I just took a shop towel sheet and sprayed the sheet with some brake cleaner to clean it up.

New vs. Old

Dirty
Clean

Step 3: Install the new 4th Gear Pressure Switch / Sensor

Do not overtorque it! Place the new sensor & gasket in, and thread it in gently. Torque it to 14 ft.lbs.. only! Secure the connector over the new sensor & secure the harness bolt that you removed.

Reassemble all the removed parts, battery, intake tube. Make sure you put everything back and tap all the secure points down - intake housing bolt, throttle body clamp, header breather tube & spring clamp, engine cover clips, etc..

Step 4: Remove driver's side splash shield

This requires some tab removal from the driver's side fender / wheel well and two 12mm bolts if I remember correctly. The way you remove the tab is to use a flathead to pop out the neck; pull the neck all the way back and the tab / clips should come out easily. I had 4 bad clips that I couldn't replace due to dry rot, which is why I recommend buying add'l clips.

Step 5: Remove the 3rd Gear Pressure Switch / Sensor

Once the splash shield is out of the way, you should clearly see the sensor behind the subframe support & front motor mount. Lay some shop towels down because some ATF will leak out (maybe 2-3 ounces). Unclip the connector & remove the sensor. Clean up the area and ATF before installing the new 3rd gear pressure sensor / switch.

Step 6: Install the new 3rd Gear Pressure Sensor / Switch

Install the new pressure sensor. Remember.. Only 14 ft.lbs of torque! Clean up any residual ATF on the case with some brake cleaner. Put the connector back on and put the splash shield back up with the appropriate clips and your done. 

Broken Tabs / Clips

Recommendation: Change ATF

Since you're already in there.. access to the ATF fill bolt & drain bolt are cake. The ATF fill bolt is on the top of the image below, painted blue and is marked ATF on top. Looks like a 22 or 24mm socket size. You'll need a funnel. I didn't host a picture of the drain bolt but it should be female 3/8" drive bolt, bottom of the case and will probably be marked with paint as well. I'll host pictures of both later on tonight. 

Well that's it.. If I missed something let me know. I hope that helps some of you out.. and if you're still wondering WTF? Here's some reading material.

http://tl.acurazine.com/forums/showthread.php?t=721508 <-- Click Link

10-19-2009

It's been a couple of months now and it shifts beautifully. I'm much happier. It still slips in 1st before upshifting but other than that.. it's like new again. No jerkiness or spotty rpm's / hydraulic pressure while cruising.

6-2-2015

Almost 6 years since I changed them..
Time to change them out again