2000 Sienna Starter Mystery -- I'm at My Wits End

ignition
toyota
engines
sienna
relay
starters

#1

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.



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 – Bennet – Austin TX


#2

I think you need to replace the solenoid wire. A broken (burnt) wire with just one strand intact can read 12.55VDC but won’t carry the current (amperage) needed to operate the solenoid. That’s why a direct connection from the battery operates the starter just fine. If the wire checks OK then the problem may be dirty (burnt) contacts in the ignition switch. I think the original problem caused the problem with the wire or the switch.


#3

Thanks – good ideas.

Visually, the insulation on the solenoid wire seems ok, not brittle or burned, and the wire itself is pretty flexible…but I realize that’s not the best way to evaluate it. I’ll see if I can trace out where that solenoid wire starts from and try to determine what’s going on with it.

Is there any way to test the ignition switch or must it be removed from the car first? Also, do you know what’s involved with getting to the ignition switch; is it inside the steering column or somewhere external? - thanks - Bennet