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I have a 2010 IS250C that has refused to raise the top back up two times now. The first time was back in January and took it to the dealer to get it fixed. For those of you that know all the details, it had fault code B0252A. It was a microswitch that was not working, telling the computer that the rear window was not locked down. The tech swore at it and lubed it and the top worked again.
A couple of days ago, we finally had another warm day and put the top down. Come time to put the top up and no go. Back to the dealer. Same fault code. This time the tech said that a spring that operated the switch was out of place and and put it back. Top works again.
Now comes the bad part. I was informed that if the switch fails again, I will have to replace the part. That doesn't sound so bad, I mean what does a microswitch cost? A dollar at radio shack, $10 at Lexus? Noooo... Try $2500 plus labor!: eek2: Because the switch attaches to the rear window, Lexus has decided that it can only be sold with the entire rear window assembly.
Can you get the microswitch off, or at least get any numbers off it? There are a lot of microswitches out there, very likely this is much less than $10 if you can figure out which one it is.
All microswitches are either Normally Open (NO) or Normally Closed (NC). You might be able to defeat/bypass the switch by attaching the wires to the switch together (most likely), or cutting the wire and taping it off. That will tell the computer the rear window is always locked down, and depending on the programming, the computer might ignore it when it doesn't need to be locked down.
You might also be able to replace the microswitch with something more common by modifying whatever holds the microswitch. A competent alarm installing or auto electronics shop should be able to figure that out.
I have not seen the switch or how it is mounted in the mechanism. The service manual shows it as a NO switch but the challenge is to get to it. From what I understand from the tech at the dealer, you have to have the top standing straight up in order to access it. I'm not sure which side of the car it is on, so I will have to so some investigating.
just got redirected to this thread by you in one of my posts.
have you been to a number of repairers? usually you might be able to find someone that has done this kind of work before. even if 9 say no it cant be done, you just need that 1 to say yes who can replace the part for cheap. try and find one who has worked on convertibles or luxury cars a lot
I understand what you are saying and agree totally. The vast majority of mechanics are simply parts replacers, not true repairmen.
I think I may have located the microswitch. The one I saw was a standard, buy it at Radio Shack, microswitch. There are 2 screw holes for mounting the microswitch and instead of using screws, the switches are sort of rivited to the hinge mechanism. But based on what the Lexus Technican said he did the last time, (reposition a spring that had popped out of place), I may not have looked at the correct switch as there wasn't any spring with this switch.
I decided to update this thread. Back in May the top refused to go up again so I took it to the dealer for the $2500 reaming. They replaced this mechanism with a motor and 2 arms on it and that seemed to take care of the problem as it worked all last summer and fall.
To be able to really see the mechanism, you would have to remove the headliner. Without doing that, all you can see is just a tip of it.
But I'm not happy that I had to buy a $1100 mechanism for a lousy microswitch. Gotta have a fat wallet to own a Lexus.
This is all useful stuff. Should any of us encounter the same problem, it would be useful to know the spec of the microrswitch - either a manufacturer's part number or a photograph of the switch. Microswitches are marketed as generic parts across a range of manufacturers usually with a range of actuators as well as contact types.
The microswitches on the convertible top mechanism are made by a division of Panasonic called Panasonic Electric Works. It is their ABJ series, also called the Turquoise series. It is switch number 39375. When looking up the switch, you look for ABJ39375.
However, I could not locate this specific switch. The ABJ series is not super common. Mouser Electronics lists about 50 different ABJ switches but not the one Lexus uses. Newark Electronics lists only 6 ABJ switches, 3 of them labeled "no longer available". One of the switches, ABJ19151, has the note "Special ABJ Switch for Pontiac Coil". It is special order, no pricing available, no return, no refunds. I suspect that the one that Lexus/Toyota uses is also a special design just for them and Toyota will not allow it to be sold to the public.
The only thing that seems to make this switch special is the arm that operates the contacts. In the photos that I have seen, the arm is attached differently than on the switch Lexus uses, not to mention the shape of the arm. As Lexus uses the microswitch, it is mounted in a holder (the black part in the photo) and the operating arm is pressed in (it is removable) between the switch and the holder.
The switch mounted in its holder seems to be the same size as a standard microswitch sold all over. I suppose that if you bought one of these standard switches with an arm attached that you could bend it to match the one Lexus uses.
At the beginning of the spec sheet there is a breakdown of the switch number (the 39375) telling you what features the switch has. The Lexus switch uses numbers not listed. Same goes for the switch at Newark Electronics described as for a Pontiac.
The switch on the top of page 8 of the spec sheet is close to one of the switches used in the Lexus.
Thank you so much for the information! It looks like the arm is part of the holder and the micro switch itself is generic? If it is, I wouldn't mind stocking up on it. Perhaps the arm can be removed from the Lexus microswitch and mounted on the generic one?
Usually these are so simple that they never fail, so it's unfortunate that you get charged thousands when the part you really need is only a few dollars.
BTW, do you still have the old mechanism in the picture above? I am willing to buy one of each type of microswitch and send them to you if you wouldn't mind testing out which ones fit on that part? Will be really useful to know.
Here are some tidbits of info that I either: A) learned, B) figured out or C) made my best guess at.
The operating arms arms should come off. There is an opening in the black holder (the left end as my photo shows the switch) and you can see a tab on the metal arm that you would push in so you could pull the arm out. I have not tried to do this.
I looked at several websites and did not find any so-called generic switches that were the size of the actual microswitch. Everything was larger Then I tried to find a switch that was the size of the both the switch and the holder, and again, everything was larger. If you were to find a generic switch, you wouldn't be able to attach the original operating arm.
I am not certain as to exactly how the switch mounts in the holder. On the end of the holder opposite the operating arm, there is a hook type tab. But the wires going to the switch pass through an opening on the bottom of the holder and after the wires were attached, the opening was filled with epoxy. This effectively is holding the switch to the switch holder. Whether you can dig the epoxy out without destroying the holder is a good question.
It would be nice if Toyota would sell the little wire harness with the 2 switches on it. One screw attaches each switch to the mechanism and 2 or 3 zip ties attached the wires to the mechanism. You don't need the metal plate.
I still do have the mechanism. However, based on what I was able to find out, or maybe not find out, I think the switches are so unique in size that only the Panasonic switches will work. There is very little extra room to try and put a different size switch in, not to mention trying to make an operating arm.
I am having an issue with my top and I'm wondering if this is the same thing. The code is similar though not identical here is what code came up:
Not sure if this is the same thing, or even if this is what is actually wrong with the top. Most of the time the diagnostic says it's clear.
Briefly here's the issue:
If I start the top sequence to open and hold it down, sometimes it will get halfway through and then hit me with the Op Suspended and freeze, other times it will get almost all the way open and hit me with it, and sometimes it will complete like normal (though this is seeming rarer and rarer). Similarly when trying to close it it does the same thing.
When it first started happening last fall I took it to a Lexus dealership and they came back at me with this bull**** of "it could be the motors and that'll be 2 grand, or the clamps and that could be 4k, or the computer itself and that could be 6k" and it's like I took it in and you can't even tell me what exactly is wrong with it. Anyone got any ideas or know a place or person in the Nashville, TN area who works on Lexus Convertible tops?
I just dropped 2k to fix an electrical problem, and when I get the car back can't even get the top to work correctly. This will probably be the last Lexus I ever own (and who knows how much longer that's even going to be) which is a damn shame because the IS has been my favorite car up until I actually bought one.
I am having an issue with my top and I'm wondering if this is the same thing. The code is similar though not identical here is what code came up:
Not sure if this is the same thing, or even if this is what is actually wrong with the top. Most of the time the diagnostic says it's clear.
Briefly here's the issue:
If I start the top sequence to open and hold it down, sometimes it will get halfway through and then hit me with the Op Suspended and freeze, other times it will get almost all the way open and hit me with it, and sometimes it will complete like normal (though this is seeming rarer and rarer). Similarly when trying to close it it does the same thing.
When it first started happening last fall I took it to a Lexus dealership and they came back at me with this bull**** of "it could be the motors and that'll be 2 grand, or the clamps and that could be 4k, or the computer itself and that could be 6k" and it's like I took it in and you can't even tell me what exactly is wrong with it. Anyone got any ideas or know a place or person in the Nashville, TN area who works on Lexus Convertible tops?
I just dropped 2k to fix an electrical problem, and when I get the car back can't even get the top to work correctly. This will probably be the last Lexus I ever own (and who knows how much longer that's even going to be) which is a damn shame because the IS has been my favorite car up until I actually bought one.
03-16-16, 10:36 PM
convertible top problem
