I have a 2000 Montero Sport its a 3.0L engine. We had to replace the battery, after we put in the new one it started acting up. The alarm doesn't work anymore, when I try the remote to turn it on the thing doesn't turn on or off, its like its dead. and because its connected to the power locks they don't work either. The horn doesn't work,which is also a part of the alarm and the inside lights aren't working either. The panel ones are but the other ones don't, (like the reading lights and inside ceiling light). AND now when we drive it, the transmission is off. The car reads that it is in between Neutral and Drive, it keeps highlighting both of them. and it only goes to 2nd gear. What could have happened? all we did was change the battery? Could someone PLEASE give me some input? and the switch to where you put the diagnostic machine is not reading anything, its like its dead/burnt out. I took it to the Dealership and they were going to charge me 80 bucks just to look at it...I said forget it! I took it to another mechanic and she said that the relay..the one by the battery might need to be replaced and the transmission sensor might need to be replaced. I don't know what do you think? Please help!