Mastermike

Hi guys new to the site looking for the solution to the PO720 code. Has anyone had this code and fixed it? If so how did you fix it? any threads or old posts could be helpful also. 2000 Maxima manufactured 6/99 with 3.0 and auto trans. Transmission code RE4F04B FN37. Vin # JN1CA31DXYT51**** Thanks for your help. Mike

maxiiiboy

OK, we like to help - but we prefer people to help themselves, rather than being spoon-fed.

So, here are the essentials:

• We are all very lucky, because unlike with many other cars, Nissan allows the FSM (the Factory Service Manual) for the Maxima to be freely available off the internet. Use the 2nd line in my signature to get it, and download all sections. Do it now!
• The FSM provides the diagnosis for all codes. It also suggests the steps to remedy the problem encountered.
  • Of special importance are the following sections: IDX (Quick Reference Index), GI (General Information), EC (Engine Control), and AT (Automatic Transmission).
• For any ODBC code, you start in section "EC", or Engine Control:
  • First, you search for code "P0720". Here, the table on pg. EC-10 will refer you to AT-114 (that's section "AT", page 114.)
  • Next, you go to pg. 114 of AT. Here, in the middle of the page, are the recommendations:
    • Check the following items.
      - Harness or connectors
      (The sensor circuit is open or shorted.)
      - Revolution sensor
• Clearly, the Revolution Sensor (and/or the associated circuitry/connectors) are the prime suspects.

With this help, you should be able to do all this on your own.
Good luck!

User1

Put two of these in and call it a day.

https://www.ebay.com/itm/31935-8E006...72.m2749.l2649

Mastermike

Thanks for all the information Maxii. Looks like the vehicle speed sensor, (VSS) (AKA) the revolution sensor will be the culprit.

Mastermike

User1. Put 2 of them in? I only see one on the trans behind the cover of the driverside wheel. Is there another one? I only ordered 1 from the ebay link you sent.

User1

There are two for my 2003 RE4F04B, but only one for your 2000 RE4F04B, apparently, so yeah, you lucked out and saved a whole $17 dollars. Or $240 if you paid stupid dealer price. Congratulations.

03
https://www.nissanpartsdeal.com/part...agram=319_A002

00
https://www.nissanpartsdeal.com/part...html?PNC=31935

User1

And yes, I had this code. And yes, replacing this sensor/s fixed it.

Mastermike

Thanks User1.. I hope this does the trick. I will post results after I install the part. In the odd event that the connector is the problem where can I purchase that?

User1

It's not the connector. Spray it out with carb cleaner or something if you need to, Ensure good contact.

Mastermike

10-4. I was just thinking of the worst case scenario like broken or burnt wire in the connector. I will clean and use dielectric grease on the connector. Thanks everyone and Ill post again after new part is installed. Mike

User1

Never ever use dielectric grease, ever. Do you see that crap on anything that just rolled out of the factory? That's right.

Mastermike

10-4

MichMaxFan

Why? I've used it with no negative results in my trailer harness connection. And I've used a specific cleaner and lubricant for wire connections that worked wonders on a totally stuck Nissan connection. It not only allowed me to actually get it off but it's a butter smooth connection now. Granted, the spray i used was for auto wire connections and not specifically dielectric but I've had no problems with dielectric.

Theslaking

Spark plug boots

Mastermike

Going to do a Transmission flush and refill before I replace the transmission sensor. The sensor is for the Po720 code I have making my transmission slip, randomly come out of gear, or not shift at all.,, Solution right now is : Turn car off for a couple minutes, restart and drive away till it happens again. The sensor Part # 31935-8E006 should fix this problem. The question here is what is the best ATF to use for the 5th gen Maximas? 2000 Max, 3.0, automatic

maxiiiboy

https://www.walmart.com/ip/Valvoline...allon/15125768

Mastermike

WOW! What a mess. Drained trans fluid. It was muddy looking so decided to drop the pan and change the filter also. Changed the filter. ( why in the hell are there 3 different sized bolts for the trans filter ) ? Pan magnets had 1/4 inch of fine metal shavings. Cleaned pan and magnets with brake clean and reinstalled with new gasket. Going to refill with fluid Maxiiiboy suggested. The sensor # 31935-8E006 will be in tomorrow. I will install and start driving. I hope this trans is still good. I will report back tomorrow. Thanks everyone..... Mike

User1

The Valvoline stuff is what I've been using too. Hope the work cleared up your issue. Let us know!

Mastermike

Transmission fluid and filter changed yesterday. Part # 31935-8E006 to fix code # Po720 installed this afternoon. After 50 miles of driving, I have no check engine light and transmission has been shifting normally with no problems to report at this time. I'm not going to call it fixed yet till i get a few hundred miles on it. Thanks User1 , maxiiiboy, and all others that contributed. I will report back in 250 more miles to let everyone know how its going. Mike

User1

Good to go!

Mastermike

175 miles no problems. Still shifting smooth and no check engine light. I am about to call this thing fixed and put this thread to bed.

User1

Drain and fill tranny again in 5k. Happy travelling!

maxiiiboy

And then again in another 5K - and then every 30k thereafter.

Child_uv_KoRn

iTrader: (7)

Drain n fill is wasting money diluting old fluid, though. Disconnect cooler hose and pump all of the old crap out.

User1

Do you drain with plug AND pump or do you even bother pulling the plug?

User1

That's about the schedule I intend to keep. Either keep it really, really clean, or never change it at all. Change it too late and all you do is open up a can of worms.

Child_uv_KoRn

iTrader: (7)

Dump the pan, refill (4 qts), pump it out while switching gears, refill, pump a couple more qts out (till you see fresh fluid), refill, test drive, top off

Castrol high mileage or walmart dexron high mileage with lubegard. But pretty much anything will work (castrol import, mobil 1, any dex compatible fluid), but those two HM are the cheapest.

15 for a gallon? YES PLEASE

User1

I'll do my best not to get my d!ck stuck in the sunroof.

Mastermike

Calling it fixed guys.. Over 500 miles now with no check engine light or transmission slippage. shifting smoothly as it should. I will change trans fluid in 5,000 miles and every 30,000 miles after that. Thanks for everyone's help! Mike

User1

Awesome. Just changed my tranny fluid last night with oil change. Shifts are butter. Things last for as long as you take care of them.