stereo and a/c blew

i turned on my car and the stereo went on as usual but when i tried to turn on the heat the stereo and a/c-heat stoped working. happened, did a fuse blow and if so, which one? thanx

For future reference, always post the Year, Make and engine size of your car so that a diagnosis and help is much easier (Example: 1994 Geo Metro, 3 Cyl Engine, Manual Trans). Assuming this is a 89-94 Geo Metro, Does this car have the original factory radio in it? If not, The aftermarket Radio in the car could have been installed with the power wire feeding off the Heater Circut in the car......Thus overloading it and blowing the fuse when turning both on. NEVER Install a larger value fuse in a circut to compensate for added aftermarket items that have been added to the car (Stereos etc..) The aftermarket Stereo needs to be on it's own circut with it's own fuse if it draws that much extra current. Here's 2 pics of the Underdash fuse box on 1989-1994 Geo Metros (Later years may be the same???). This fusebox is under the Drivers side dashboard. Notice that the "ACC Fuse" lists the Radio as being on that circut.......But the HTR (Heater blower motor) is on it's own fuse Circut. Pull each fuse in the underhood fuse box and inspect them for being blown. If you find any, replace them with the SAME Value fuse. If it still blows the fuse....You've got a wiring problem that's overloading the circut. Again, is this a Factory radio or a After market CD Player Etc....?

Underdash fuse box

http://i25.photobucket.com/albums/c83/MrBBody/FuseandRelayBlockbelowInstrumentPan.gif

Fuse Descriptions

http://i25.photobucket.com/albums/c83/MrBBody/FuseDescriptions2.gif

sorry it's a 1990 geo metro 3 cyl engine with a manual transmission. I'm not sure if it's the original car stereo or not, it's a pioneer that has am/fm and a tape deck. also, the diagram doesn't fit my cars fuse layout, mines under the hood and it only has 10 fuses. it has 2 a/c relay fuses, 1 fuel pump fuse, 1 f1 relay, 2 acc 15amp, 2 30amp, 1 40amp, and 1 60amp? do you have a diagram for a 1990 geo?

#1. The Pioneer Stereo is NOT The original factory car stereo in your Metro......It's an aftermarket Stereo.......Check and See where the "Red" and "Orange" wires of the Pioneer Stereo are connected too and post back?

#2. The underhood fuse box is for the AC relays, Fuel Pump etc.... You DO have another fuse box like the one in the picture above, Under your drivers side dash, just above the brake pedal. This is the fuse box with the Heater and Acc (Accessory) fuses in it......You'll have to get down under the dash with a flashlight to see it (And the fuses) clearly.