2006 Sienna LE problem: failed to start

When you say that the engine failed to start, do you mean that the engine would crank and not start, or would the starter not engage and you just heard clicking or nothing at all, or would the key not turn in the ignition?

Is the key the original key or is it a duplicate?

When you say "no treatment, no answer," do you mean that the dealership just ignored you or was the service department unable to duplicate the no-start condition? What does you copy of the repair order say?

Thanks for the reply.

The key (original) turns normally, and I can hear the starter sound but the engine wouldn't start. At one time, I parked the van and went into a store for half an hour, when I came out, I could not start the van.

The service depatment at the dealership couldn't reproduce the problem, and they didn't provide an explanation of the van's behavior.

So far this problem happens when the van is warm, that is,

1) start the van from cold (parked for hours), no problem. 2) drive and then park; 3) after a couple of minutes (say less then 30 minutes), start the van, it won't start (hear the starter sound, engine won't start). The brake pedal is hard to press down-- this is problem? 4) Take out the key, re-insert and start again, this time the engine starts successfully.

The reason the dealership could not provide an explanation is that they did not experience the problem first hand. With lemon laws common in every state, it would not be in anyone's interest to make blind guesses.

Your description of the conditions when the no-start condition appears seems pretty clear to me. Did you ask the dealership if they tried under the same operating conditions? Have you tried driving to the dealership, parking, and then trying to re-start while there so that someone from their service department could see what is happening?

The problem sounds little like a problem with the engine immobilizer system. By any chance, do you have a Mobil Speed Pass device on the key ring? If so, try removing the Speed Pass and seeing if the problem goes away. I read somewhere (IIRC, there was a service bulletin) that in some cases, the Speed Pass was interfering with the engine immobilizer system.

Try your spare immobilizer key. The immobilizer key has a small chip inside which is activated by radio frequency emission from a box in the dash for a short time during start, the key sends back a burst of data that is unique to your vehicle and the vehicle starts. It could be the box or the key, or an engine problem. Your dealer should be able to find it if they try. Go back again.

Thanks Ray and dbu, I feel better now with your words.

1. Speedpasss: no, I don't have such a device on the key chain.

1. The dealership didn't try under the same conditions I just described, because I finally found out those conditions after I visited them.

2. It really might be the immobilizer issue. I'll go back to the dealership next week to ask them to try under those conditions, and give you an update.

Thanks again.

Hi, Ray and dbu: Good news, I figured out the "bug" by myself today! It is indeed the key problem:

I drove the van out and, surely it won't start after I stopped for 10 minutes.

I finally noticed that the Immobilizer light was still flashing even after the key was turned to "On" (the position just before ignition). This could only mean the van did NOT recognize the key.

I changed to another spare key, the Immobilizer light was OFF, and yes, the van was started easily.

So it's the key problem --- although I still can't understand why it happens when the engine is warm. I'll go to the service department very soon.

Thanks for the update!

I think those keys are about $100 to replace so if it's still in warranty be sure they supply you with a replacement even though you have a spare.

I keep my spare in a secret location so that if I am away on a trip and loose the main key it I will not be without a key. I keep a standard key (non-immobilizer) in my wallet to get in the vehicle, then with tools I get my spare immobilizer out.