Tranfer case stuck in Low range

[carnajr]

Range Rover Sport 2007 TDV6. The transfer case was recently rebuilt and the gearbox serviced with new filter, LifeGuard 6 fluid is used. There have been issues since then with the transfer cse getting stuck in low range. The IID Gap tool has the general list of errors that are on other vehilces on the internet, eg. Terrain Response U416-94, U403-94, U421-94 and Transfer Case P0915-00. The Gap tool will clear the faults but they come staright back, this is the same as others outr there.

The mechanic shop managed to get the vehicle out of low range but the Terrain Response errors persisted. I drove it around the block a bit cleared faults, turned vehicle off and on (not in that order but you get the gist) and then the alerts went away and the car was alert free. The transfer motor was tested on Friday night via selecting Low and High (gearbox in Neutral as required) after 2 cycles it decided to throw the error again, so it's now back to the alerts but at least it's in the shed this time.

All of the electrical conctors on the transfer case have been cleaned, the transfer case motor was heard runnning during the testing, the transfer solenoid was heard clunking doing it's job, but alerts will not clear.

After searching the internet for a few hours, a solution pointed to possible gearbox adjustment needed. The Gap tool was plugged in and the gearbox transmission gear reading checked. When the car is in Neutral the gearbox reports it being in 2nd gear. All manual gears are selectable and the correct gear shows on the dash, it's just Neutral that is 'wrong'. The car doesn't move in Neutral so it's not in gear

Could this be why the transfercase fault appears, it cannot do anything if the gearbox reports 2nd gear when it needs neutral ???? Is there a senor in the gearbox that needs to be/can be adjusted to calibrate the ECUs and the mechanical position ?? Are there readings on the Gap tool that would confirm if

Or is it simply the transfe rcase motor has failed and needs to be replaced? I do not want to have to open up the gearbox again for 50K Kms.

Any help is greatly appreciated

[Graeme]

A procedure exists to adjust the gearbox range sensor although the WSM refers the reader to LR diagnostic equipment.
I would certainly expect an incorrect neutral notification to affect a transfer case range change.
The WSM documents the procedure to calibrate the transfer case range selector.

Below are saved notes of mine.



Transfer case in neutral - pre MY10 L320











original issue was the transfer box was in neutral, a scan through the service manual gave a calibration procedure of





depress accelerator to the floor insert key turn till dash light illuminate without starting,





press and hold high range until you hear it engage or longer than 5 seconds






turn off key, release accelerator










wait 15 seconds insert key start car










select low range.

[carnajr]

Thanks Graeme, that was done was done but it din't clear the faults. Either the Gap tool isn't quite that smart or there is a sensor gone faulty. It's starange the Gap tool never shows a Neutral on the transmission gerabox gear. I'll send an email to thier support and check that I'm interpreting it correctly.

[carnajr]

Investigations continue. The vehicle was driven to an independent landrover mechanic and checked with an Autologic . No clearing of the faults was possible, nor calibration of the transfer box motor.

The transfer box motor has been removed and checked. The motor does not spin when power is applied (details of the pinouts from topix were used), nor can the nylon gear selector be turned by hand. Most internet searches with a resulting fix point to the motor being faulty.

Any other suggetions are appreciated.

[carnajr]

The issue continues, it has since been checked by a European car mechaninc with thier equipment to no avail. The car had been put into high range manually and driven to their workshop. They could find no faults. While there the vehicle was put into low range to demonstate the problem (it's a short drive home). All of the faults appeared, the car was left running during the change. They could not clear the faults or calibrate the tranfer case motor. The car has since returned to the gerbox mechanic who has removed it and checked all operation on the bench. They suspected the solenoid, measured the resisitence and came up with 0.8ohms. Searching the internete suggests this is not right but there's nothing definitive.

Does anyone know the resisitence of a new solenoid??? I've got workshop manuals but havent found it.


Searching the internet is not delivering much in the way of a solution. This vehicle only had an oil leak, the transfer case and range change was working perfectly just two week prior. We have a trip coming up in less than a month......