Where do you start to finding the cause of a problem with 1998 Toyota Corolla radio?

1. Check the fuses. The first thing you should do when troubleshooting a radio problem is to check the fuses. If a fuse is blown, it will prevent the radio from receiving power. The fuses for the radio are located in the fuse box, which is usually under the dashboard on the driver's side.

2. Check the wiring. If the fuses are all good, the next step is to check the wiring. Make sure that all of the wires are properly connected and that there is no damage to the wires. You can use a multimeter to test the voltage at the radio harness.

3. Check the antenna. If the wiring is all good, the next step is to check the antenna. Make sure that the antenna is properly connected and that there is no damage to the antenna wire. You can test the antenna by connecting it to another radio.

4. Check the radio. If the antenna is good, the next step is to check the radio. You can do this by removing the radio from the dash and inspecting it for damage. You can also try connecting the radio to another power source to see if it works.

5. Take the car to a mechanic. If you are unable to find the cause of the problem yourself, you can take the car to a mechanic. A mechanic will be able to diagnose the problem and repair it.

Here are some additional tips for troubleshooting a radio problem:

* Make sure that the volume is turned up.

* Try turning the radio on and off again.

* Try changing the source of the radio (AM, FM, CD, etc.).

* Check the balance and fader settings.

* Try resetting the radio.