01 tiburon, alarm reset? wont start

You could try disconnecting battery, leaving overnight and then inserting ignition key and switching on before reconnecting the battery.

It has sometimes worked for me but in reality it seems you probably have an alarm immobiliser fault you need specialist help with.

Disconnect the battery for 2 minutes to reset the alarm system then hook it back up. Sounds as if the alarms kill switch was engaged, which will prevent the car from starting.

did the engine accidentally get turned on by key when timing belt was off or anything that could have moved crank or cam shafts.did you hook battery back up..never know,is their something you have to do to reset computer after you disconnect battery...

Contact AVITAL company. This sounds like the alarm is killing the ignition or fuelpump circuit. Sometimes there is a sequence used in alarm resets and you should know it if you are out in the Boonies without a Cell signal.

Leave the battery disconnected for an hour.

In the meantime, go into the fuse panels and search the fuses and verify none are blown.
After an hour, make sure you CORRECTLY hook the battery up again and then see if that dont start it...

try dissonecting the battery cables for at least 10 -15 mintues then hook them back up and giver a try

you can get it to crank but you just won't be able to use the keyless function without going back to the dealer first locate the ecu fuse in the fusebox under the dash, pull it out but don't put it down. Next put your key in the ignition and start turning over the motor, now the car won't crank or push oil through the motor with the ecu deactivated so don't hold it for too long. Now as your turning the motor over, reinsert the ecu fuse. The car will fire to life...you will have essentially reflashed your ecu so people with tuned ecu's beware. Your keyless won't work but hey at least now you can drive to get it fixed...as for the naysayers, yes I tried this on my tiburon and it still works fine so don't worry...good luck

try to open and close your car trunk

Check your terminal connections, if they are loose they will need to be inspected for breaks. If they are broken you will need to replace the connection. Make sure they are clean and free of corrosion.

Other possible Problems
If the car wont turn over your starter could be bad.
If it turns over but wont start it could be any number of these problems.
Coil Pack
Plug Wires
Spark Plugs
EBX (Engine Brain Box)
CBX (Chassis Brain Box)
Crank Sensor
Fuel Pump
Fuel Rail
Fuel Injector

Good luck

Possibly the alarm cut-off switch? or Ignition key switch (or wires) going bad?

But you mentioned you tried to jump start it and it did turn over?
IF so, you could have severe corrosion or loose connections of the battery cable both at the battery and at the termination points, such as ground and starter motor.
Check that the battery wires are tight and clean at the battery posts and at the other end.

Again the No lights suggests either the alarm cut-off, or an absolute disconnected battery cable.

Finally, it could be ignition fuse, Check fuses. Ignition key switch.

What makes this hard is that you suggest it would turn over with another battery connected. This makes no sense.

Good luck