# 4wd not working



## gordymac (Mar 29, 2013)

I have an 01 Pathfinder with electric 4x4 shift.. everything was working fine the other day not it won't go into 4WD..

If the switch is set to 2wd, auto, 4 hi or 4 lo, makes no difference.. the indicator light works (I'm assuming that is just tied to the switch though) but only still have 2wd.. if the rear tires spin (even when locked in 2wd) the 4wd amber warning light comes on and the indicator light shuts off.. 


Now.. like I said it was working fine then it stopped.. the only thing that happened in between was... the transmission line where it goes into the rad, one of the pipes was rotted off and let go.. I couldn't find a new rad without ordering and taking 3-5 days here, so they suggested looping it out through an external addon air cooled transmission cooler.. I guess it is working because the tranny is shifting fine, no slipping or anything, but I don't know.. that is the only thing that happened and the 4wd stopped working immediately afterwards.


Everyone I ask says that the tranny has nothing to do with the 4wd, but I feel like it has to have something to do with it since when that messed up I lost my 4wd.. any ideas?


----------



## smj999smj (Jan 1, 2006)

The trans issue shouldn't have anything to do with the transfer case and might just be coincidental. You said the 4WD warning light illuminated, so there should be stored 4WD codes which will assist in diagnosing the problem. A generic OBD II code reader will only read engine codes, so stopping by the local auto parts store won't work. You'll need to take it to a Nissan dealer or an independent shop with a scantool that can access 4WD trouble codes.


----------



## gordymac (Mar 29, 2013)

But.. the only time I can get that light to come on is if I spin the tires.. if you shut off the truck and turn it back on, it resets.. light goes out until the next time you spin the tires. And I forgot to mention, for the first 10 mins or so of driving, it doesn't happen, it seems once it warms up is when that happens..

If I were to go out, first thing in the morning, spin the tires, nothing happens.. 10 mins later if I do it, warning light comes on.. just like its too hot or something?


----------



## smj999smj (Jan 1, 2006)

Found this TSB which might be helpful:

Reference:
NTB04-074

Date:
June 9, 2004

2001 - 2002 PATHFINDER; 4WD WARNING LAMP COMES ON INTERMITTENTLY
APPLIED VEHICLES:
2001 - 2002 Pathfinder (R50)

APPLIED TRANSFER CASE:
All Mode 4WD (Model ATX14A)

APPLIED VIN:
2001 vehicles, all VIN's
2002 vehicles built before JN8DR09Y(*)2W 747550

APPLIED DATE:
Vehicles built before June 28, 2002

IF YOU CONFIRM:

The 4WD Warning Lamp comes on intermittently and/or flashes,

ACTION:
1. Check the All-Mode 4WD system. Confirm the following:

a. There are no DTC's for the All-Mode 4WD system.

b. All 4 tires are the same diameter (same size around the tread area).

c. There is no malfunction with the transfer fluid temperature sensor circuit.

d. Transfer fluid is not overheated.

2. If there are no other malfunctions, replace the transfer case Main Oil Pump.

PARTS:
PUMP ASSY. P/N: 31340-0W415


----------



## smj999smj (Jan 1, 2006)

There is also a 4WD self-diagnosis procedure you can perform. You can e-mail me at [email protected] and I can send it to you; put "RE: 01 Path 4WD self-diagnosis" in the subject line. Or, you can download a factory service manual online. One source I know of is linked below, but you need to e-mail the site owner for a password:

Nissan and Infiniti Service Manuals


----------



## gordymac (Mar 29, 2013)

I bet the transmission is over heating and it is causing the transfer case to become hotter as well, let me try some things.. might be on to something here.


----------



## smj999smj (Jan 1, 2006)

gordymac said:


> I bet the transmission is over heating and it is causing the transfer case to become hotter as well, let me try some things.. might be on to something here.


I doubt it. Anyone who is familiar with the R51 radiator failure situation knows that there are many of them who are driving around using only the auxiliary cooler and bypassing the radiator cooler without any issues. Also, since the transfer case oil does not come in contact with the transmission fluid and even though the transfer case is bolted to the transmission, I would have to imagine that the auto trans would have to get so hot in order to affect the transfer case fluid, that the the trans would likely experience problems or complete failure before the transfer case would experience any issues. That's my opinion, FWIW.


----------



## gordymac (Mar 29, 2013)

I just find it extremely weird then.. 4wd worked for years, 12 years or so, never a problem with it.. parked truck, noticed a small leak was coming from the pipe on the rad, wiggled it and it snapped right off... put in new line and everything, started it up, go to move it and had a problem... pretty big coincidence if its not related at all... 

The tranny seems to be working fine and shifting fine, but if you touch the steel line you will burn your hand, it is VERY hot.. hotter than one would think it should be.


----------



## smj999smj (Jan 1, 2006)

The trans cooler line coming out of the trans will usually be in the 200-250 degree F. range, depending on operation conditions. The oil in the pan should be in the area of 175-200 degrees F. Keeping in mind that 212 degrees F. is the temperature required to boil water, you can see that it does get pretty hot. You can always replace the radiator (which I would recommend anyway) and see if the problem persists. Personally, I would do the self-diagnostic test and see if there are any codes (you don't need a scantool for this) and would take a good look at the TSB. Generally Nissan releases TSBs when they see a fair number of similar problems and since your vehicle falls within those vehicles affected, it's something to look at.


----------



## smj999smj (Jan 1, 2006)

BTW, I sent that self-diag procedure to your e-mail.


----------



## gordymac (Mar 29, 2013)

Yeah I plan to replace, just waiting on the part now, but still trying to fix whats not wokring.. and thanks I got the email, will try it.


----------



## gordymac (Mar 29, 2013)

Alright.. so I tried it.. I get 19 flashes total..

Flashes once, then on about 2 seconds, then flashes 18 times after with about .5 of a second between each flash..


----------



## gordymac (Mar 29, 2013)

Oh.. also.. if I have it in 2wd and spin the rear tires, the 4wd warning light comes on, and the indicator shuts off, but it will switch to 4wd hi, 4wd lo, auto, and 2wd and work.. I tested it about 30 times today, and even though the warning light is on, it was still shifting and working fine.. doesn't make sense?


----------



## smj999smj (Jan 1, 2006)

gordymac said:


> Alright.. so I tried it.. I get 19 flashes total..
> 
> Flashes once, then on about 2 seconds, then flashes 18 times after with about .5 of a second between each flash..


Refer to the picture in the procedure I sent you. The start of the code sequence is the 2.5 second long flash. The short, 1/2 second flashes indicate the code. If there is a series of short flashes separated by a 1 second pause, then this indicates multiple codes stored. If you are saying the one flash before the short flashes is about 2 seconds long, then it looks like you have a code "18" and have to check the ATP switch, wait detection switch and neutral-4LO switch circuits for a short or open. If you are getting a short, singular flash followed by a slight pause and then more short flashes, this would mean you have a code "1" for the revolution sensor short or open circuit and would need to check that first. This is why it's very important to pay attention to the flash timing to make sure you get it right and don't go off on a wild goose chase diagnosing the wrong code!


----------



## gordymac (Mar 29, 2013)

No, it is the 2.5 second long flash, then 18 short quick flashes.. then repeats, it keeps going over n over though.. so.. I have an 18... 

What is involved in fixing/replacing that?


----------



## smj999smj (Jan 1, 2006)

I e-mailed you the info for the diagnostic procedure to check the ATP switch, wait detection switch and neutral-4LO switch and circuits. I put "RE: 2001 Pathfinder transfer case diag" in the subject line.


----------



## gordymac (Mar 29, 2013)

It seems that if I try and switch to 4wd Hi, it doesn't engage.. if I switch to 4wd lo, it works flawless.. then I can switch from lo to hi and it will work, as long as I do 4wd lo first...

This is mind boggling for sure.


----------

