That can be a bit of a chore there and we aren't even SURE that's where the problem is. There may be more than just the head unit on that fuse and something ELSE could be drawing from it and causing teh problem as well. He needs to get a test light or VOM and see if there's a short to ground on the power wire, radio lighting wire, or constant 12 to the radio.

 

if it is the fuse box under the dash it sould be labled and if i remember correctly the hot wire from the sterio goes directly to the headunit.

 

Have to look at what the fuse actually goes to. usually there are more than 1 thing to each fuse. Besides if you read he says it's under the hood not under the dash..

 

oops got the stock amp fuse and the head unit fuse mixed up sorry. this complicates it a little just because the sterio wire runs in the harness from the under t hood fuse box to the head uni you can try and trace it and test it but it will be difficult.

 

ill get pics up as soon as i have free time to tear the dash outta my car again. i dont have a power cable wired to the battery directly, i am using the old harness also. the only wire that i have running directly to the battery is a positive wire for my amp. to clarify, it IS the fuse under the hood that is blowing, it is labeled "radio". ill get photos soon.

 

definate short between the fusebox and the headunit also if u have the time pull the headunit out and see if the fuse on the back of it has blown by chance if it dose not have a fuse you might havd a problem there wired backwards i have done it was given a jvc harness for a rockford fosgate they have the same fittings and what u said happened. but it sounds ike you may have the keyswitch wire crossed or shorting out not the constant becuse it is not until u try to start the car right.

 

the fuse on the head unit has not blown. it is a 15 amperage, and when i put a 15amp fuse under the hood it still blows, ill try to trace the wires as far as i can, maybe one melted :-P, they are still stock wires from the old headunit.