Page 1 of 2

4wd engaging in 2wd !!??

Posted: Mon Sep 23, 2019 6:19 am
by nismopath
Lately as I have been riding on the highway, my 4wd warning light will come on and my square display that is inside the tach goes blank. I have the knob set to 2wd.
Any ideas on what’s going on ??

Posted: Mon Sep 23, 2019 7:13 am
by disallow
I would check for any ABS codes. Sounds like a loose wire or connection.

Posted: Mon Sep 23, 2019 10:15 am
by nismopath
Thanks. How would I find that out? There is no check engine light going off.

Posted: Mon Sep 23, 2019 12:15 pm
by disallow
ABS light on?

Posted: Mon Sep 23, 2019 12:22 pm
by nismopath
No it is not on.
The is issue happens sporadically though, on a 20 minute drive it may come on 2-3times max. Each time for 30seconds and then turn back to normal.

Posted: Mon Sep 23, 2019 7:33 pm
by smj999smj
There's a transfer case self-diagnostic procedure that can be performed to get the self-diagnostic codes via the 4WD light flashes in the case you don't have a scan tool that can read the codes. It's listed in the factory service manual. NICO Club's site has free access to their Nissan FSM's.

Posted: Sat Sep 28, 2019 12:56 pm
by nismopath
Can I just go to autozone or one or those places to scan the code ? Or do you mean there is something else I should do?

Posted: Sat Sep 28, 2019 4:53 pm
by smj999smj
nismopath wrote:Can I just go to autozone or one or those places to scan the code ? Or do you mean there is something else I should do?
Parts stores usually use a generic code reader that just read "P-codes." To get codes for the transfer case, you need to have a capable scan tool or do the self-diagnostic procedure listed in the FSM.

Posted: Sun Sep 29, 2019 12:33 pm
by nismopath
Ok great. Now what is a FSM ?

Posted: Sun Sep 29, 2019 4:06 pm
by smj999smj
"Factory Service Manual":

https://www.nicoclub.com/nissan-service-manuals

BTW, do you have the standard transfer case or the AUTO mode transfer case?

Posted: Mon Sep 30, 2019 8:09 am
by nismopath
Oh ok. Thanks
Mine has 2wd, auto, 4hi and 4lo

Posted: Mon Sep 30, 2019 8:36 pm
by smj999smj
So you must have an "LE" model with the AUTO mode transfer case. A problem that sometimes occurs is that there develops a poor contact between the harness connector terminal and the pin of the transfer relay, which controls the electric transfer pump. The AUTO mode transfer case has a wet clutch and uses both a mechanical pump and an electric fluid pump. When in AUTO, the electric pump operates at speeds below 35 MPH, at idle and also when in reverse; other than those conditions, the electric pump will not run.
The transfer relay, which, FYI, is the same P/N as the relay for the air suspension in the Armada, is located in the engine compartment, not far from the brake master cylinder, and is on a small bracket that attaches to the side of the engine compartment with a single, 10MM head (6Mx1.0) bolt. It will have two harness connectors plugged in to the single relay. In many cases, you can unplug the relay, clean up the pins on the relay with a small file, tighten up the terminal in the harness connector with a pin so it will apply more tension, and put it back together and erase the codes for the fix. In my case, it worked for about a year and the problem re-occurred due to corrosion on the relay pin, so I ended up having to replace the transfer relay, which was about $35 and is part # 25237-EA000.
If this is your problem, when you check for codes in the transfer case, you will get line pressure codes.

Posted: Wed Feb 12, 2020 7:42 am
by nismopath
What section would it be under in the service manual ? I found a couple diagnostics while searching but I don't think I found the right one. Is there an acronym that they use or what would it normally say ?

Posted: Wed Feb 19, 2020 9:29 am
by nismopath
I installed the new one and same thing happened. I haven’t driven it around the block yet so it may go off, but just curious if I need to reset the ECU or do anything after installing the new relay? Or should it have just gone away?

Posted: Thu Mar 12, 2020 1:41 pm
by nismopath
is this the right self-diagnostic ? I tried twice and nothing happened. I got it from another site when I googled


1. Warm up engine.
2. Turn ignition switch “ON†and “OFF†at least twice, and then turn ignition switch “OFFâ€.
3. Move A/T selector lever to “P†position.
4. Turn 4WD shift switch to “2WD†position.
5. Turn ignition switch “ONâ€. (Do not start engine.)
6. 4WD warning lamp should turn ON.
If 4WD warning lamp does not turn ON, refer to DLN-72, "Diagnosis Procedure".
7. Move A/T selector lever to “R†position.
8. Turn 4WD shift switch to “2WDâ€, “4H†and “2WD†in order.
9. Move A/T selector lever to “P†position.
10. Turn 4WD shift switch to “4Hâ€, “2WD†and “4H†in order.
11. Move A/T selector lever to “N†position.
12. Turn 4WD shift switch to “2WD†position.
13. Move A/T selector lever to “P†position.
14. Read the flickering of 4WD warning lamp.