Recently after my battery on my 2003 disco HSE died, my radio and speakers stopped functioning. I wanted to replace the head unit anyways from the standard one (w/nav) and did so; however to no avail, the speakers will not function. To ensure it was not the new head unit, I wired a free sitting speaker to it and it worked. Now.... the attempt to bypass the HK amp and wire the speakers directly to the head unit, caused the Disco to go into limp mode. I rewired the amp back in, and it came out of limp mode, but of course, still no sound.

Any solutions?

 

Are you positive it was the amp you took out or bypassed?

Removing the amp would not affect the M&S in any event so I believe it is a coincidence. It is more likely to be the battery failure and so you'll need to remove the stored codes.

 

It was the Harmon Kardon amp under the driver seat that was removed (which caused the M & S flashing lights)

 

Did you remove any fuses under the drivers seat?

Check the LR RAVE workshop manual electrical supplement wiring diagrams. RAVE is available online on this website. There may be common fuses to both systems. I would be amazed if removal of the HK amp would impact upon the autobox electrical system.

PS: also check to see whether you have disturbed/disconnected a common earth ground when you removed the HK amp.

 

No fuses were removed when I removed the amp. So I do agree there has to be some kind of disturbance/grounding out under the seat. I have looked at the exact replacement online, I am wondering if a simple replacement would fix the lack of sound and avoid the potential limp mode.

When the battery died, the radio went into anti theft mode, so I just never fooled with it because I didn't know the code. Eventually, the radio wasn't coming on at all, prompting for a code or anything... prior to the dead battery, everything worked fine.

 

John,

Just a heads up, I've got an 04 HSE that had the nav system in it and when I replaced my head unit (kept the amp & speakers for now) I found out the hard way that all of the wiring diagrams I was finding online and from places like Crutchfield were for non NAV equipped rovers.

I wound up doing about two weeks of reading on the forum to find two useful but vague posts out of about 200 that I read. I finally wound up with the wiring diagrams from the RAVE. Google the D2 electrical manual. I'm not very electrically inclined but thru some trial and error and using the RAVE charts I was able to wire up my new head unit.

So go check out the RAVE cause some of the wiring that you think you know exactly what it's doing might be for something else. F'ing Nav in the HSE's is not only antiquated but the wiring makes installing anything new a complete b*tch to do!

 

I just slapped in an aftermarket stereo into an 03 with the OEM Nav head unit. I just connected the red/blue wire to the Blue/white wire on the aftermarket harness (metra harness had it in the wrong spot). After that it was a done deal.

Aftermarket just needs 12+ constant Yellow Wire for memory, 12+ switched power Red Wire, Black Wire for ground. Then the Blue/white from the aftermarket stereo needs to connect to the Red/Blue wire to power the OEM Amp.

 

Yep. But I"m a little slow with reading electrical diagrams and it took me a while to figure that out on my own. The OP is messing with the amp under the drivers seat and I'm wondering if the wiring is marked differently there too. If he figures it out it will just give me a leg up when I get around to replacing the amp & speakers.

 

Well, isn't that amp on top of the transmission ecu??

Imagine if the wiring to the transmission ecu got nicked or jiggled loose. That transmission ecu signal is required to prevent limp home mode, right?

The transmission ecu needs a good xyz signal from the transmission itself, and then the transmission ecu has to send the "all good" signal to the engine ecu...otherwise, limp home mode.

So I'd be looking at that wiring/connection under the amp. Or heck, imagine if the installer thought that *both* boxes under the seat were the amp and pulled them both...so maybe there isn't even a transmission ecu at all in your Disco anymore!

Guaranteed limp home mode if any of that happened.