2011 Navara D40 - Stuck in 4Lo, can't disengage back in 4H neither in 2WD. 4Lo Light Flashing

[Navara_MKD]

Hi All,

I have problem with my Navara D40 spain build 2011. Recently I have driven in 4Lo, with differential lock function. On snow. steep road. in Backward (revers speed) but also straight in 2nd 3th gear. All went good. But after that, i can't put the car in 4H, neither in 2WD. The gearbox is stuck in 4Lo. High RPM and low speed. On the board the light 4Lo flashing when try to put in 4H, and also light 4Lo flashing together with the ''2 front wheel symbol'' when i try put in 2WD. Also ESP is ON all the time. I assume is ON because it is in 4Lo mode

I put the car on Delphi diagnostic tool and only the following errors appear, which i think are not connected with the gearbox and transfer switch:

C1163 Steering Angle Sensor
C1143 Steering angle sensor, circuit faulty

P1856 Vehicle dynamic control - unknown status

Those errors above i think are close connected with an car strike(impact) towards side walk pawement and road fence with the right front bumper

I have made self diagnostic with help of service manual i found here on the forum and the result was - NO FLICKERING on 4WD light - that means PNP switch or 4WD shift switch ?

So what are those items and how to troubleshoot them? also what step by step procedure can undertake to exclude some other possible faulty sensors switches, motors solenoids etc?

Can i somehow put the car in 2WD manually to be able to drive it easier on asphalt till i troubleshooting the issue?

Thank you all in advance

Igor

 

[Old.Tony]

In my car, which is only slightly older than yours (electrics are going to be the same), I have to have my gearbox in neutral and my foot on the brake to take the vehicle out of 4LO (not just putting it INTO 4LO, it's also coming OUT).

If you are doing it that way, there may be an issue with the control servo on the transfer case. This sits in the back of the transfer case and is basically just an electric motor that turns 90 degrees first, then a further 180 degrees second (2LO to 4HI, then 4HI to 4LO) and reverses that for the change back to 2WD. You can remove the servo and use a large screwdriver to turn the mechanism inside to test it.

I find that if I'm on a firm surface (compacted dirt or bitumen) and I've been turning a little it will sometimes not come out of 4LO very easily. I usually drive forward slowly turning left and right, stop, put it in neutral and press the brake and try again. 4LO to 4HI usually cooperates fairly quickly.

Sometimes 4HI to 2HI takes a bit of time. You can safely drive on sealed surface in 4HI, and while driving (below 100km/h) switch to 2HI and sooner or later it will disengage. I find that same slow movements - sometimes reversing too - helps it disengage faster.

 

[landmannnn]

The other option is to jack up front wheel, with the engine running but main gearbox in neutral, switch it to 4hi. Then see if you have released any wind up by turning the wheel in the air by hand.
You should hear the actuator on the transfer box operating when you operate the switch.
If no good, turn the engine off, remove the actuator from the t box and turn the mechanism on the t box with a pair of pliers.

 

[Navara_MKD]

In my car, which is only slightly older than yours (electrics are going to be the same), I have to have my gearbox in neutral and my foot on the brake to take the vehicle out of 4LO (not just putting it INTO 4LO, it's also coming OUT).

If you are doing it that way, there may be an issue with the control servo on the transfer case. This sits in the back of the transfer case and is basically just an electric motor that turns 90 degrees first, then a further 180 degrees second (2LO to 4HI, then 4HI to 4LO) and reverses that for the change back to 2WD. You can remove the servo and use a large screwdriver to turn the mechanism inside to test it.

I find that if I'm on a firm surface (compacted dirt or bitumen) and I've been turning a little it will sometimes not come out of 4LO very easily. I usually drive forward slowly turning left and right, stop, put it in neutral and press the brake and try again. 4LO to 4HI usually cooperates fairly quickly.

Sometimes 4HI to 2HI takes a bit of time. You can safely drive on sealed surface in 4HI, and while driving (below 100km/h) switch to 2HI and sooner or later it will disengage. I find that same slow movements - sometimes reversing too - helps it disengage faster.

Hi Tony

Thanks for the replay and kind explanation

First i forgot to note that it is manual gearbox. I assume that your navara is automatic and thats why you need to be in neutral with brake pressed.

from the beginning of the issue i try with slow movements, turning left right. stopping. going backwards with the knob selected on 4Hi but no luck. it is not releasing

I found the black transfer case box with motor in it. I removed it, Than with screwdriver try to turn around the axle inside the gearbox. Left it went only 1/4th and right only 1/2 with feeling on spring returning force back. the position of the axle you can see on the photo attached

also switching the 2wd 4Hi 4Lo knob inside, is not giving signal on the servo motor and it is not spinning when it was removed from the gearbox

But next that i found out were one cable with connector disconnected from a sensor switch and second cable with connector broken from the sensor switch above it. you can see them on the second photo. but those sensor switch are not those 3 around the transfer case box marked with different colors which are easy approachable. these 2 are more in front and looking rear. it is easier to approach them from inside the cabin where the gear shifter is located in the middle. I have no idea what those sensors are and what is their function. With two of them disconnected and no alarm given on pc diagnostic it is strange

I have connected again the first sensor but the second one i need to fix the connector somehow and see if something would change

also i need the remove the three sensors TRANSFER BOX SWITCHES and check them with instrument are they working as should expected ( NO, NC)

 

[Navara_MKD]

The other option is to jack up front wheel, with the engine running but main gearbox in neutral, switch it to 4hi. Then see if you have released any wind up by turning the wheel in the air by hand.
You should hear the actuator on the transfer box operating when you operate the switch.
If no good, turn the engine off, remove the actuator from the t box and turn the mechanism on the t box with a pair of pliers.

Hi Landmannn

thank you for the notes

By jack up front wheel you mean to lift the front chassis in air and wheel to be free. I've done that but still wheels are engaged and cant be turned around in air by hand. Also 2Hi or 2WD switch is not operating anything. just flashing the 4Lo on the dashboard

then i removed the black box called actuator, from the transfer box, and with screwdriver try to spin the axle in it. but it is not spinning 180 degree in order to disengage from 4Lo to 4H. Maybe during spinning the axle i need to move little but the vehicle front back in order somehow release something inside the transfer box