So a couple of weeks ago my 2016 LR4 became a giant brick in my drive way. Upon trying to start the vehicle, I get the "Gearbox not in park" warning message upon many other systems not being available. I tried replacing the GSM with a refurbished one off of Ebay with no luck. Upon further inspection I noticed that Fuse F30 (Automatic Transmission 10Amp) is blown. I replaced that and immediately it blew. So I am guessing I have a ground short somewhere?

I should add when I started down the repair process I did notice the dreaded sunroof drain line leak issue and flooded passenger foot-well area. I replaced the drain line elbow, drained/air dried everything out. So wondering if maybe that was the culprit that started the issue above?

I've currently got the CJB still unplugged, the ECM (or is it TCM?, silver box behind battery) unplugged and quite a few other connections near the CJB unplugged and the fuse (F30) is still blowing/shorting out. Where should I be looking to track down this electrical short? Could a fault such as a bad solenoid in the transmission be causing this? Any other ideas? Could this be a starter/solenoid issue? I'm not the best when it comes to tracking down electrical issues. Any help and guidance would be much appreciated!

 

I see fuse 30E appears to be shared by the transmission control and the transmission “switch” (I assume the gear selector). More interesting is that the gear selector appears connect to the fused harness right in that area of the passenger compartment where the leak happened, possibly on the backside of the junction box.

 

Thanks so much for the response @jlglr4 ! I did check those connections by the CJB and on the CJB out. Cleaned up the small amount of possible corrosion. Didn't seem to solve my issue though. Today, I crawled under the truck and disconnected the connection (C0193) directly at the transmission. Interestingly enough my fuse isn't blowing anymore. So I think that means I might have a bad solenoid or perhaps the connection sleeve needs to be replaced? Out of curiosity, what source did you use for the diagrams?

 

Sorry to hear it. You could try replacing the connection, but I think it’s more likely a bad solenoid or something on that side of things. I’ve not been into the transmission before.

The connection diagrams are floating around on the web - I think on some of the overseas forums. I’ve posted up links here before. If I can find them again, I’ll repost.

 

Hello there, having the same issue currently and although this post is a year old, wanted to know how you got it fixed or if you just moved on from the problem. Cheers

 

Was there ever a solution found for this? I’m having the same issue. Thanks!

 

The last one we did 2016 lr4 8speed HP it had a coolant leek in the rear crossover and kept blowing fuse F30 ( grey plug on top of bell housing in rear of engine bay ) full of dried coolant with short in Valve block , The fix clean connector really well and replace valve block and new pan and fluid ,cost to rebuild old valve block more than cost of new one ,Was told by Land Rover engineering the valve block have been known to just short out with out the coolant leek.

 

Awesome, thank you.

I just fixed my rear crossover that had been leaking. The next morning I went to start the truck, I got “not in park” and a bunch of “lost comms with transmission” faults. That’s when I noticed fuse 30 was also blown. Now, fuse 30 blows immediately as soon as battery power is applied.

I took everything that I did the day before back apart to make sure I didn’t damage any wires while I was repairing the crossover …nothing there. Tested every connector in the harness …nothing. It was only when I unplugged the main mechatronic connector at the transmission that fuse 30 stopped blowing. I figured that since I fixed the leak and everything in there finally had a chance to dry out, that dried coolant would be the problem.

Right now I have the trans pan off and I’ll be taking the valve body out today. I planned on testing for a shorted solenoid or TCM, but I’ll clean that gray connector again and see what I can see.

Thanks for the info!