2001 4.6 Battery Change problems

I recently changed the battery in my 2001 HSE. Since then the radio only partially works, I can select stations but can't adjust the volume. If the key is not in the ignition, the stereo and the volume control on the steering wheel work fine. A soon as I insert the key in the ignition, the front speakers stop playing and I can not adjust the volume. Only the rear speakers work. In addition, the GPS screen is blank, and the power light on the unit in back does not come on. The unit will repeatedly eject and pull the disk back in but wont function. Any ideas what is causing the problem, and how I can reset/repair them? It seems like a short or loose connection somewhere but I have no idea where to look. Any ideas?

I have the same Range Rover you do. When you change the battery you have to keep constant voltage to the leads you take off the old battery or you have to enter codes into your vehicle. A reat pain in the ass, but I did it myself. I think your owners manual has the codes in it.

I wrapped some 16 guage wire leads from the battery leads in the RR, to the posts of the battery I was removing. Negative post to negative lead, positive post to positive lead. Once I got the old battery out without losing contact, I dropped in an Optima 800 red top and put the leads on the new battery and removed the wires from them.

Really - what a PIA

This is also something I should have put in my post above. - I changed the battery out and now the radio needs a code.

Well I have bad news , P38's had stickers under the hood that warned not to disconnect the battery untill the red led stopped blinking on the NAV unit, No fix . you'll need to replace it. and all LR radios need the CODE for the head unit to work, you might have something else going on at your head unit. you'll need a dealer to Diagnos it now.