Apologies for bringing this topic up again, but your thoughts would be welcome.

I replaced the alternator last week, after it started throwing out 17v+ and causing mayhem, but now appear to have problem with the transfer box motor.

Symptoms include:

'Transfer box neutral' on the dash
Intermittant orange flashing lo-range light
Car won't go above 3rd gear
Can't switch to manual mode with the gear stick

IID Tool Faults include:
0x8D Transmission Interface Bus Fault
0xEF No TXU1 recieved from Transfer Box ECU
0x59 Transmission Emergency program fault
0x85 Can bus transfer box timeout: general fault

I took the motor off and did some tests today, using previous posts from RRPhil and others as a guide. When I measured the resistance of the potentiometer I got:

Low range - 1.64 Kohms
Neutral - 3.24 Kohms
High Range - 5.23 Kohms

Low and Neutral seem to be around normal, but the High Range reading seems to be 0.4-0.5 Kohms over the expected of 4.7-4.8 Kohms. Do you think the extra resistance is enough to cause the above faults or have I missed another possible cause such as the ECU? David

2012 Range Rover Westminster 4.4TDV8
2004 Range Rover Vogue 4.4 V8 (LPG) (Not quite gone)
2021 Mazda CX-5
2003 Porsche Boxster

NV225 transfer box shift motor potentiometer issues tend to give the error message “noise on actuator signal” or similar, and I don’t see that on your list. Have you tried Fuse 37 at all?

Phil

Hi Phil

Thanks for the reply. I've had that fault code on and off during the last year when switching from high to low range and back again. No obvious indication there was a problem other than the fault code on the IID toll though. I'm sure it will come up again if I get this motor working.

Tried the Fuse 37 fix before I took off the motor, but no luck. Will try agin tomorrow after refitting this motor, otherwise may try to get a cheap second hand one before spending the money on getting this one refurb'd, to see if it is the cause of my present woes.

Cheers David

2012 Range Rover Westminster 4.4TDV8
2004 Range Rover Vogue 4.4 V8 (LPG) (Not quite gone)
2021 Mazda CX-5
2003 Porsche Boxster