Had this fault code pop up. Did some research and it appeared to be a DTML heater circuit code. Read some other pages about DTML pumps, and if the heater circuit was bad, it was most likely the pump. I purchased and installed a new Bosch DTML pump (leak detection pump), started her up, and there’s a P1481 code again after clearing. Need some help on this gentlemen, anyone have info? Secondly, last year my transfer case went out on me. I purchased a used one from Monte-Rovers. They said they sent me a 2004. But after replacement, I could not shift from hi to low. While doing the DTML, I found a hanging 2 connector which appears to be the Neutral Sensor connector. Does anyone know where this connects on the harness? I took it to the shop that did the work and they looked all over, but could not find the connector.

connector

 

Which diagnostic tester did you use to read fault code P1481? That code doesn't sow up in the Discovery 2 RAVE manual.
That looks more like a an O2 sensor connector but I could be wrong.

 

Aren't the O2 sensor connectors round, not square?

 

the older RR O2 sensors were round. The D2 O2 sensors are rectangular with rounded corners. Fronts can be orange or aftermarket grey. it's the inside tab that designates front or rear connector....

Don;t know if interlock solenoid plays a role in you not being able to shift HI to LOW...

 

I used an ICarsoft sold by Atlantic British for Land Rover. It said it was a Land Rover specific code. I cleared, and it came back.
The Oxygen sensors are new (last week) Denso’s. They’re fine. New MAF as well, and Land Rover fuel cap.
The connector is identical to the Neutral Sensor on my old transfer case. I’m just not sure where it connects on the harness since I didn’t do the work. Shop says no place for it to connect.
personally I think it connects up top on one of the multi-plugs, but I’d hate to have it dropped again to have to search for it.

 

Below is a pic of the old transfer case with the connector that is not connected. One is a yellow and green wire, the other brown and yellow. Both are in a blue shrink wrap.

 

If your truck did not originally have a CDL then there may be extra switches associated with the 2004 transfer case to tell the system that it’s locked. I’m not 100% sure if the gray connector in your pic is from a switch or from a harness, I assume the former, and in this case there would be a pair of diff lock switches in the 04 that would not have anywhere in your 03 to connect to. The sub-harness that runs from the shift console down through the trans tunnel and onto the trans/xfer case is different between between CDL and non-CDL (IE 03 and 04).

This post of mine from a couple months ago has some relevant info, just ignore the numbering in my first post as I had it wrong. Switches 3 and 4 in my first pic are the diff lock switches, they are wired in parallel so if one fails the other still completes the circuit. An 03 truck with no CDL would not have anywhere to connect these two switches and the switch connector does in fact look similar to the neutral switch. It may even be the same switch (part number).

I’m not sure what other people who upgrade an 03 to and 04 transfer case do when it comes to the wiring but if you got an 04 transfer case with a locking diff then you can trace the wires in the main harness and either fab up some pigtails to connect to the existing switches in the case (most likely the dangling connectors), or install a manual switch somewhere to tell the ECU/TCU/BCU that you’ve engaged the CDL. You may want to lock the diff and put a meter on the switch(es) to see if they’re functioning before fabbing up pigtails. The switches are apparently a high failure rate item (hence the redundancy) and are a major PITA to swap out due to their position.

https://landroverforums.com/forum/di...39/#post711461

 

Have you confirmed they are the same wires colors from the neutral switch on the old transfer case and the connector that’s hanging down? In that case, there should be a plug up there somewhere to plug the neutral switch into. I Wouldn’t think it would require dropping the transfer case again to find. There’s a bunch of room up there to hunt around.

Edit: As I understand it, the interlock solenoid in XRAD's post above is energized whenever the transmission is in neutral, and only then can you select Hi-Lo in the transfer case. This is accomplished by passing ground from the TCU up to the solenoid itself through connector 0683 in the pic below. The neutral switch in the transfer case lights the light in the cluster through connection 0684 but does not inhibit selecting Hi-Lo if disconnected. You should be able to use a small mirror, or even feel around on the top of the transfer case to make sure these are connected. If they're not then you've found the problem. If they are then you should put the trans in neutral to see if the solenoid plunger is pulled in. You can also can proceed to the CDL post above if you want.