I married into a 2004 discovery 2. I put in new head gaskets because it would not pass emissions; valley pan gasket was the issue but why not do the whole thing since I was over half way there anyway. For whats it's worth I do all my own wrenching. Did a little off road driving with it but felt it did not perform well at all and put little to no more thought into it.

Fast forward - On a whim I bought a 2003 and took it off road. Man it chewed up wash-out ditches and was a beast off road compared to the 2004. Did some digging and discovered shady folks were covering up the three amigos. I know that to be true. Luckily they did not break the LEDs.
This is the first vehicle I have owned that requires a ABS reader so if there is anyone in the Atlanta area that wants and can assist with retrieving ABS codes let me know. I have done a lot of work on both discos so I'm up to sharing what I know as well.

I hope this helps someone in the future when looking at a disco for purchase. The TC,ABA, and DHC should self test when you turn the key.

 

that is called the out of sight out of mind method