4lo wont engage

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00pathySE
Posts: 165
Joined: Wed Aug 12, 2009 6:02 pm
Location: Ontario

4lo wont engage

Postby 00pathySE » Mon Aug 30, 2021 3:07 pm

Hi all,

Im having a problem gettting my Pathfinder into 4lo. The issue is when i shift from 4hi to 4lo while in neutral, the 4lo indicator light flashes a few times and then the screen goes completely blank followed by the 4wd warning light. I need to restart the vehichle to clear the issue.
I have cleaned and checked, tightened the transfer relay that is located near the brake booster, and also checked codes using 4wd self diagnostic per the FSM. I have codes "19" and "21" which refetence the actuator motor and relays. Not sure where to go from here as to diagnosing. 2wd,auto and 4hi seem to be working or at least have no warning/error lights. Any advice or suggestions are much appreciated. Thanks.

My issue is identical to this video:
https://m.youtube.com/watch?v=L98h4IKRY_U&t=110s


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smj999smj
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Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Re: 4lo wont engage

Postby smj999smj » Tue Aug 31, 2021 4:33 am

Most of the problems (which are few) with the AUTO mode transfer case are usually caused by the transfer relay, itself, whether it be resistance between the relay contacts and the pins of the harness connector or the relay itself. Other than that, we seldom have any issues with them. My own, 2006 LE, had the same issue with the contacts; I cleaned them up and it worked for about a year, but I ended up having issues and replaced the transfer relay. If you look at the the top of the page, you can see a link to the service manuals section. It would be in the factory service manual where you would find the diagnostic info for the two codes you have. That would be your best bet to actually trouble-shooting the problem.

00pathySE
Posts: 165
Joined: Wed Aug 12, 2009 6:02 pm
Location: Ontario

Re: 4lo wont engage

Postby 00pathySE » Tue Aug 31, 2021 8:45 pm

Thanks for the post smj. I checked with multimeter per fsm the relay and the wiring to the relay along with the hi and lo relay and wiring and it all checks out. Also pulled the neutral 4 lo switch and it checked out ok too. I am now thinking of pulling the transfer motor to check that. My question is does anyone know if the motor operates for both 4hi and 4 lo? Because i dont have any issues getting into 4hi, only 4lo.

00pathySE
Posts: 165
Joined: Wed Aug 12, 2009 6:02 pm
Location: Ontario

Re: 4lo wont engage - SOLVED

Postby 00pathySE » Thu Sep 02, 2021 11:30 am

Always, Always, Always check your fuses first :oops: . The last couple of days werent a complete waste of time I guess. I now have a much better understanding of how the 4wd system operates and how to check switches and relays for continuity. My problem in the end was the blown 20 amp fuse next to the transfer hi an lo relays under the hood. Happy that Nissan was kind enough to supply a spare under the glove box.

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palmerwmd
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Location: Mid Atlantic

Re: 4lo wont engage - SOLVED

Postby palmerwmd » Thu Nov 11, 2021 10:02 am

00pathySE wrote:
Thu Sep 02, 2021 11:30 am
Always, Always, Always check your fuses first :oops: . The last couple of days werent a complete waste of time I guess. I now have a much better understanding of how the 4wd system operates and how to check switches and relays for continuity. My problem in the end was the blown 20 amp fuse next to the transfer hi an lo relays under the hood. Happy that Nissan was kind enough to supply a spare under the glove box.
Thank you for this update.
I am sure it will help other members! :D


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