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Toyota Sienna Electrical Problems



  • hershghershg Posts: 2
    Having exact same problem on our 2007 Sienna LE.
    Wondering if you've made any progress in getting it fixed.
  • Sorry we have finally given up. After numerous trips to the dealership and they could not "reproduce" the problem the only thing they could tell us was that they would note it in our records. If you find someone that can give you an answer please let me know. My husband has made a video on his camera phone showing the dashboard lights but the mechanics still have no explaination. Good luck!
  • I had similar problem. Driver window on 2000 Sienna--intermittent stopping. Use suggestion at your own risk. I bought spray can of electrical contacts cleaner--check trade stores that cater to electronics technicians. I removed window control assembly and (can't remember exactly how far) disassembled until I could see actual contacts. Sprayed clean & reassembled. Be really careful with dis- & reassembly. Don't try unless you're willing to replace if you mess it up.

    Worked fine for a while (months) then had another failure. Haven't tried cleaning yet, but only failed a couple of times. This last time it would go for an inch or 2 and stop. Then I cut off engine, restarted car, got a couple more inches. After several tries got the window up. Don't know why! Only failed a few times over several days, now ok again...BUT

    Now problem others have developed--all dome lights and electric locks failed. Replaced fuses--no help. This seems to be a rare but repeated problem, per internet search. Only solution I've read about was replacing the ECM. Seems drastic! And expensive!
  • I have a 99 Sienna and the dash board light (the one that illuminates the speedometer, tach, etc.) went out. Also the backlight that illuminates the heating & A/C controls is also out. Makes driving in the dark difficult when you can't see how fast you're going.

    I've checked the owners manual, and every single small fuse in the vehicle (actually removed each one and looked at it, and put them back). I can't believe it's a bulb that would control both the dash light and heating and A/C controls back light. I've checked both fuse boxes under the hood and the one behind the small change box near the left knee. Thanks!
  • Whenever I try to unlock the door (either using the keyless entry or by hand manually) the alarm system goes off. You must then turn on the veh. to get it to turn off. This just started the last two days (got quite cold suddenly). Also noticed that the door locks are behaving a bit strange. One other thing my wife noticed was that twice now when you try to turn on the veh (with the alarm going off) it won't turn in the iginition (like its locked). When you play with the locks (push lock unlock etc.) the iginition will usually then work. This does not happen every time! In fact, only my wife has had this experience (twice). Any Ideas?
  • ateixeiraateixeira Posts: 72,587
    Replace the actual fuse. Some times they look OK but they are not. A hairline crack may not be visible. Try it - they cost pennies.
  • wwestwwest Posts: 10,706
    Tell your wife to remove the other "chipped" key from her key ring.

    This exact same thing happened to me. Ask yourself: did I use the "odometer/trip meter" recently? That little twisty knob under the odometer (for some reason) doubles as a dimmer switch for all of the Indiglo dashboard panel lights (which includes the blue back light on the radio/middle display), although it isn't marked as such and although you already have another dimmer dial to the left of the steering wheel. You might have accidentally twisted the trip meter instead of pushed it and therefore dimmed your display panel and radio backlight to zero. If you do this, the OTHER dimmer switch won't work, which led me to believe it was a fuse or something worse.

    A mechanic was going to charge me $1600 to replace the power supply unit! So apparently it is not widely known that this happens, even among mechanics, or else my mechanic was going to keep my Sienna for a few days, then walk out to the van, twist the little trip meter clockwise to make the blue lights come back up, and charge me nearly two thousand dollars for the service. :mad:

    I'll always Google a problem I'm having with my car from now on. I saved a lot of money! :shades:
  • I have a 2001 Sienna, and I have a very similar problem. The power door lock doesn't work when car is not running... when it's running, the power door lock does work.., all dome lights and the clock light are out. What is the problemm??
    The ow
  • My problem was that on a 2000 Sienna the dome lights and door locks quit working and the headlights would only come on with the engine running (or maybe key on-don't remember exactly). (Note here--I checked and rechecked fuses. Also my dash clock was working. The clock and dome lights are on the same fuse on the 2000 model.) After rolling this around in my mind for probably a couple of months I realized that these 3 things all had timer functions. The dome and headlights will turn off after a while when unattended and the doors will relock after a time when unlocked with the remote. I figured that they all must intersect somewhere.

    I'm a pretty good problem solver & I was afraid of what a shop diagnosis of electrical problems could cost so I started asking questions of every mechanic I could find. No one wanted to help except for one friend who was willing to print out a basic wiring diagram. I finally went to a Toyota dealership and asked the shop foreman if I could examine some wiring diagrams. He pulled the book and we looked at the individual diagrams for each of the systems with problems. There was a common element on all 3--the INTEGRATION RELAY. This might more appropriately be called a "relay integration module." This device is 2 linked circuit boards that essentially tell all the relays what to do. On the 2000 model Sienna it is in a (+/-) 2.5" X 1.5" X 5" plastic case mounted on the back side of the fuse block under the dashboard. On some cars it is integrally built into the fuse block but on this car it is a replaceable unit.

    I learned that there is no way to test this part. Often technicians try to locate an identical part on another car and use it to test the system and see if that’s the problem. I checked with the Parts Department and learned that the new part was about $430! I started looking for a good salvage yard. I found one with the used part in stock for about $100. I went home and pulled and reinstalled the fuse block to see if I could actually do it. I was successful so I drove to the salvage yard and pulled the unit, popped in the replacement part, and suddenly all was right in the world. By the way—it was a good thing I pulled the part out before committing to a replacement. The part number the Toyota place gave me was not the same as on my part. I needed the actual number from my part to match the part at the salvage yard.

    I hope this helps someone.
  • I have a 01 Sienna with an electrical Gremlin. Power door has a mind of its own, have been unable to get fixed because the dealer can't fix unless it sees the problem, which happens with no rhyme or reason.

    My issue I would like help with is the dash lights. The light that illuminates the Right side and center of display (speed odometer and fuel gauge) is not illuminated in addition to the Air flow selector in the center console. This makes it difficult at night. The controls all work they are just not illuminated. I looked at the fuses and there does not seem to be one that operates just these 2 lights. Also the cigarette lighter doesn't work either but that is not as much of a concern since I do not smoke.
  • eric55eric55 Posts: 2
    2008 Sienna Limited AWD. 9000 miles. Dead. No power to dash, dome lights, head lights or anything. Doesn't "click" with the key. Meter on the battery says it has 12.7 volts. It drove fine just an hour prior to attempting to start it.

    I measure the 12.7 volts at the main power bar in the fuse box under the hood, so it leaves the battery. There must be a main fuse or relay that delivers it to EVERYWHERE else. I can't find it.

    Anybody have any clues? BTW, I am in the country of Turkey and can't readily get to the, or any, US dealer where I purchased the car. I am sure it is in warranty, but no help there. Nothing to help me out at the Toyota website either.
  • eric55eric55 Posts: 2
    Found my own problem. I was looking too hard. When shipping a vehicle overseas, the transport company disconnects the battery. When reconnecting the battery in my van, they put the positive cable on tight, but the negative just tight enough to make contact. Over the course of the past year, the nut gradually loosened until yesterday when it lost all contact leaving no return path to the battery. Previously contact would intermittantly be lost causing the Sienna's dashboard clock to reset to 1 AM with no dicernable pattern. I am rather relieved and my clock problem is fixed also.
  • ateixeiraateixeira Posts: 72,587
    Phew, you dodged a bullet there. Glad to hear it's fine.
  • hoppinghopping Posts: 1
    2008 Sienna loses all power. Battery seems to be dead. Battery charger brings it back to life. This has happened several times usually after driving at night with lights, A/C, radio, wipers etc. all on.. First the dealer said it was the battery and replaced it. The dealer said the rear door will not drain the battery. (I sometimes leave it up with the interior lights turned off.) - all was well for a month and then same problem.

    This time dealer said it was due to rear door being left open even though the interior lights are switched off at the dashboard. The dealer said the rear door drains .5 amp even though the lights are turned off. He said it had to do with the computer trying to talk to the door or something like that.

    Does anyone know if this is true?
  • ateixeiraateixeira Posts: 72,587
    Not sure but I have heard something like that, i.e. that lights left on have killed the battery.

    I always lock the doors and make sure the lights turn off. If any door is open you get a beeping, so you know to go back and check which door isn't completely shut.
  • yatesjoyatesjo Posts: 186
    We always park the van in the garage so we don't bother locking it and have been lax about closing doors. We figured the lights shut off on their own so no problem.

    If my wife isn't going out much during the week and the van is left open for a few days the battery is drained. It happened to her twice so now we are careful to get all the doors closed. Doesn't make any sense to me why the doors drain so much power without any lights on.
  • ateixeiraateixeira Posts: 72,587
    Didn't think about the garage. Yeah, I have a car port so it's always locked.
  • tomd8tomd8 Posts: 8
    I have the same problem with my radio. It will display when turn on and then no display later but radio is still working. I have to turn off the radio then turn back on to get the display again. I was wondering did you fix your problem. Thanks.
  • hershghershg Posts: 2
    No, but, this sounds crazy, rapping your knuckles on the display when the radio gets into a bad state seems to "fix" it.
  • It sounds like you need to replace the light bulbs in the dash. It is not that hard. There are about 3 screws that you have to take out, one to the left of the steering, look up, and 2 over by the radio, in which you have to pull the plastic off there. Then the rest of the dash pops out. Then you will remove 4 screws to the display. The light bulbs that light the display are the large green screws like fixtures. The bulbs are haligens that pull out of the fixtures. There are 4 bulbs total for this area. The Air flow area is a bit more tricky. You have to remove the screws for control area, the dash will already be out of your way if you do both at the same time. There are 3 bulbs, smaller, in this area. The little push button switches have their own bulbs that you have to purchase at the dealer. The other bulbs you can buy at any auto parts store and at wal mart. Let me know if you have any trouble with this and I will be glad to help.
  • My 2005 Sienna's inside lights stopped working in the van- except the front ones - but none work any longer when doors open.
    Husband tried fuse - it is ok.
    Any other ideas?
  • All other lights work. The 10 amp fuse under the steering wheel blows immediately when I put in a new fuse.

    Any advice on what to look for or change?
  • ateixeiraateixeira Posts: 72,587
    There must be a short in the wiring that goes to that light.

    Take it (the taillight) out and clean it up, see if there's any dampness there. Check the bulb itself as well.

    I'm far from an electrical expert but I had a radio that kept doing that, and the solution was to replace the radio.
  • ccity1ccity1 Posts: 1
    My front speakers blew out a few months ago... It wasn't a volume issue, they just slowly - and seperately - chose to go... I had them replaced, and soon after my radio decided to work sometimes and then cut out (although the display stays on as if it is working fine).

    But now I can't get any sound at all (though still the same situation with the display) ... The radio 1 and 2 fuses behind the ashtray are fine... could the amp be blown?
  • wwestwwest Posts: 10,706
    That might mean you had DC, Direct Current, flowing through the speakers as the amp was in the process of failing.
  • So over the past year or so, my wife and I have noticed a problem with the radio volume. Occasionally, the volume will increase on its own and can not be turned down using the knob on the radio itself. You must use the volume control on the steering wheel. The dealership can not duplicate the problem and says that they've checked all the wiring and it seems to be hooked up correctly. I've talked to others in the waiting room at the dealership with the same issue and results. Any suggestions on how to go about fixing this problem?
  • I have a 2000 sienna and the problem started about a year ago, when I would turn my headlights on with the switch ob the column, I got nothing, but if I turned it back one click they would turn on fully, i just did not have any bright lights,but then all of a sudden it stopped working out of the blue.... the headlights do not come on at all......what do I do???
  • I have a 2004 sienna and the lights in the rear dont go on when opening the power door but only on the passengers side . When I open the doors on the drivers side they work fine .. Any idea what that is all about ??
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