[ESFlash]

The original 2000 Sienna starter got stuck on and consequently got pretty hot before the minivan was shut down.

I replaced the starter, turned the key to start and not a sound/silence. I then had my son turn the key again to "start" and measured the voltage at the incoming (small diameter) solenoid wire to the starter and measured 12.55 with key turned to "start"

I then disconnected the solenoid wire, had him turn the key to the "on" position and used a jumper wire from the hot side of the battery to the solenoid contact.

The solenoid kicked in, the starter cranked and the car started without problems.

I reconnected the solenoid wire and tried jiggling the shifter between P and N -- no help. I tried different keys...no help there. I continued to read 12.55 on the solenoid wire whenever the key was in the "start" position yet it was silent every time unless I jumpered directly from the battery.

I returned the starter got another one, had the shop bench test the replacement and it was fine. I installed that one and the same thing happened...Dead/Silent with key turned to "start" yet I read 12.55 incoming at the solenoid (small diameter) wire. Disconnected the solenoid wire, reconnected the jumper wire and starter number two started the car.

I've since installed a fused spring loaded toggle switch and start the car with the key to "on" using the toggle to kick in the solenoid.

All fuses test good. I know there is a starter relay ($71.00 from Toyota) and an ignition switch which I think is located in the steering column and most likely a PIA to replace. Any thoughts on how to replace the ignition (not keylock) switch would probably be helpful at this point.

I'd like to fix this but don't want to shotgun parts, especially electrical stuff as they are difficult to return and get your money back on.

Any ideas why I see 12.55 on the solenoid wire when it's connected to the starter and the key is turned to "start" (shifter in either P or N) yet nothing happens.....dead/silence....yet when I jumper directly to the solenoid contact on the starter from the battery it starts every time? It makes zero sense to me.

Thanks for any help

 

[ESFlash]

Sorry I posted in the wrong van forum

 

[TimL94]

The electrical reason for seeing 12.55 VDC at the solenoid and not getting the starter to turn over is that there is insufficient current to spin the starter. The voltage is there but not enough current which means there is a relay/solenoid between the ignition and the starter that is bad. It may be contacting just enough to get the 12.55VDC to the starter but not enough to pass sufficient current to the starter. I do not have a schematic so it's hard to say what it is.
I had the exact same starter problem with my original 2000 Sienna starter. I caught it early, removed that starter and took it apart. There is 2-3 gears in there that lose lubrication and get bound up. I disassembled, cleaned and regreased with light wheel bearing grease and oil in places. That was last year and so far so good. My starter did fail in the engaged posiition and I had to hurry to remove the battery lead to stop the starter.
This seems like a universal Sienna starter problem and should be monitored.

 

[TimL94]

I had the same thing happen to me but I caught it in time. I disassebled the starter gears, cleaned, relubed with light wheel bearing grease and it is working fine. Seems like a universal problem with these starters.
Not enough DC Current to turn the starter. The 12.55 VDC may be there but not enough current. Bad relay or solenoid between ignition and starter.

 

[ESFlash]

Thanks Tim -- bypassing everything and installing a high current, fused, spring loaded toggle switch that was made for this purpose, was the economical workaround that solved my problem.