Hello! I get two sets of results from the pros. One is that "error 3" means the machine glitched during reading and needs to be reset. This is done by disconnecting the power supply (Either unplug the unit, or disconnect the battery overnight). Remember, if you disconnect the battery, the ECU will reset also and will need to relearn its idle and shift settings, this takes about 50 to 100 miles of driving. The other thought on this is that it is a mechanical failure in the unit, and the unit will need replaced. Only your Toyota dealer can tell you for sure about your model and the CD unit it uses. Good luck!
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