Have Toyota Questions? Ask a Mechanic for Answers ASAP
Hello, thanks for posting
A single click when turning the key to start is usually related to a starter problem, the factory engine immobilizer system still lets the engine turn over but not start up if the transponder key doesn't match and besides you have tried spare keys. The clicking noise is the starter solenoid engaging but there is a bad contact between the solenoid and the starter motor. If the battery terminals a tight and clean and the battery is new then i t sounds like the starter needs to be replaced, this is not uncommon on either the V6 or the V8 engine, unfortunately the starter is located under the intake manifold on the V8, I have replaced quite a few of these in the past, it's a big job which involves removing the intake manifold, the starter is bolted to the block st the rear in the center of the engine.