I have a 2003 Celica and when I press the button to open the door locks they unlock but when I take my finger off the button they automatically lock again. Same thing happens when I use the remote.
Get a new battery....your system suffers from an undervoltage condition at the chassis...or an under amperage under load connection~
this includes taking a wirebrush to the other (non-clamping) side of the 1/0 battery cable and the place that it bolts to (undo the bolt please) scrub this connection point to restore the 300 cold cranking amps potential...and a reliable 12 volts to all the switches and auxiliary devices~
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