Possible causes

– Faulty Transponder key amplifier
– Transponder key amplifier wire harness
– Faulty tTransponder key ECU assy

When is the code detected?

Antenna coil is open/short

B2784 TOYOTA Description

The transponder key coil is built into the transponder key amplifier and receives a key code signal from the transponder chip in the key. This signal is amplified by the amplifier, then it is output to the transponder key ECU assembly.