Unlike other errors on the Navman S30 GPS unit, a fatal error will make the entire system on your GPS stop working. This is especially bad if there is a fatal error that occurs while you are driving or need to use the GPS unit. Fortunately, these problems are usually a one-time occurrence, but you can still take steps to correct them yourself if the error persists.
Poke the reset hole on the back of the Navman unit with a needle or safety pin. This should make it restart. If not, go to the next step.
Press and hold the "Power" button on top of the Navman until it shuts off. Wait 30 seconds then turn the device back on.
Remove the memory card attached to the Navman GPS unit. The card may have information keeping the Navman from working properly. Restart the GPS unit.
Drain the battery inside the GPS completely; do not recharge it. Once completely drained, allow it to recharge fully before starting up.
If you follow the above steps and are still unable to correct the fatal error, you may need to contact Navman to arrange for repairs. You can reach them at: (714) 204-3389, 10 a.m. to 3 p.m. PST.