editordz

Hi guys,

I just got a beautiful red '06 with only 19k miles. It's my second SC, and I can't believe how much I missed it after a four year break.

However, there's already trouble. The roof only opens intermittently. When it works, it's all good, no vibrations, nothing off track, smooth operation all the way open and close.

When it doesn't work, the red light on the open/close button will NOT light up. Nothing happens at all. I will come back to the car a few hours (or minutes) later, and it works fine. The problem never occurs for closing, only opening. Also, several times now I have closed my roof, and then immediately tried to open it again, but no deal. Those symptoms make me think it's not the ECU, but one of the sensors.

In reading everything I could find, it seems I might have to go to Lexus and pay for an hour of labor to get an error code. But before I do that, I wanted to ask here and see if anyone has an educated guess on which sensor it could be.

BTW, there is no Luxlink installed yet. I have yet to find one that includes the double-click option

Thanks all, I'm so glad to be back on the SC430 club!!

-Dan

MH6

You may want to check the switch or sensor which is located in the slot where the pull out cover in the trunk has to be in place or the top wont open. That may be making bad contact or having a problem. Or simply may not be seating correctly creating an intermittent issue.

editordz

Thanks MH6, I did that. Unfortunately, that's not the problem. If I unseat the cover, then I get the blinking red light (provided it's one of those times when the roof actually works).

JohnnyCake

The interesting symptom is that you are getting NO red light whatsoever, not blinking, not lit, nothing. Makes me wonder about the switch itself.

It's too bad you don't already have the LuxLink as that bypasses the switch.

editordz

Yeah, and not only that, but I can close the roof just fine, which would indicate the switch is fine. But then if I press the button rightaway to open (or close) it again, it's dead (no light, no action for a random amount of time).

BTW, I'm looking for a Luxlink that has the double click feature if anybody has any leads...

JohnnyCake

Disagree. It is a double pole switch. That it works to close the roof just fine indicates that half the switch is good. It could be something as simple as the wire for the open side is not consistently making a good connection. Look to physical before electronic, I've been taught -- in fact, by a moderator here.

editordz

Thanks, I definitely agree on physical before electronics. Let me clarify why I thought it may not be the switch: if I let go of the switch during the open or close operations, I can resume, reverse or continue opening and closing all I want, no problem. But as soon as I close the roof all the way, the switch goes dead, in both directions.

For instance, when I let go of the button once the roof is closed, but before the windows go up, then the close button should roll the windows up, and the open button should open the roof again. But it does neither until some random time later. It feels to me as if the ECU doesn't receive the final "roof closed" signal. But of course then I'd expect the red light on the button, which I'm not getting.

Thanks for your help and thoughts on this!

JohnnyCake

Dan, this clarification kinda changes things. I still think the lack of the light coming on is a huge clue. And just to make sure we are all on the same page, the light functions perfectly (red during operation, flashing during fault condition like trunk cover not in place) during all phases of operation when the top is working -- is that right?

As an aside (and a total long shot), have you tried disconnecting the battery for several minutes just to clear the system out? I don't think that's going to make a difference but (a) it can't hurt; (b) its free; and (c) its easy.

You may end up at the Lexus dealer, but as I recall from when I had a top problem, you must be able to recreate the problem while the code reader is connected. Codes are not stored after a successful operation. But maybe since your "failure" happens at the end, the code would still be there. Not sure on this.

If you do end up at the dealer, I'd get the code and leave. A top repair is often hugely expensive and the dealer is going to want to replace parts, not diagnose and fix. Habious saved me thousands when we (I held the flashlight) disassembled and fixed a part that the dealer would have just replaced. I think Habious does house calls, but he requires first class transportation. For my holding the flashlight job, you can send me coach.

editordz

That is correct.

I have not, but I did completely disconnect the roof ECU for several minutes, should be the same?

Yeah, that's the plan for today.

I read that whole thread, great work! Wish you guys were in the Los Angeles area, I'd send a limo

JohnnyCake

I went out today and checked out the light vis-a-vis the top opening.

Habeous suspected trouble with the valet switch, but my testing indicated that the light should flash when the valet is engaged, even though the top doesn't move.

The light is ON during the top closing but goes OFF at the moment the top is finished closing, BEFORE the windows go up. In other words, the light should be OFF as the windows are going up.

Are you getting the confirmation CHIME at the end of the top open / top close process? That is an indication the the ECU thinks the process has completed successfully. I wonder whether you are not getting that indication before the problem starts.

The fact that it clears up within minutes or hours is just weird. It may be that some sensor isn't getting pressed and then things settle and it is.

The bright side, if there is a bright side, is at least you can get the top closed. Without that ability, you really couldn't chance opening it at all.

editordz

My valet switch seems to behave exactly as it should and as you describe. As far as I can tell, the switch is fine.

That's exactly how it behaves (when it works). I have also found that when I let go off the button AFTER chime but BEFORE the windows go up, then the button may become unresponsive again for either rolling the windows up, or re-opening the roof.

Yes, I'm getting the chime every time, regardless of whether it works the following time or not.

That's exactly my thinking. It's just very difficult to track down.

Yes, you're right about that.

Well, I worked last weekend, and my wife was kind enough to take it to the dealership to get the code. Unfortunately, either it didn't throw one, or they refused to give it to her. They claimed to have cleared out some debris and lubed some parts. It worked for two days after that, but as of this morning, I'm back to intermittent function. I have ordered a roof ECU from a salvage yard. At $75, it's cheaper than another hour at the useless dealership in Van Nuys

Another nugget of information... I can also "test" to see if the roof will open by pushing the "close" button. If it works, I hear a little click that sounds like a relay somewhere in the back. It is accompanied by a second of slight dimming of the interior lights, so a load must be applied somewhere. When that happens, it means I can then open the roof as expected. If I push "close" and there is no click, no dice opening it.

If that doesn't work, I'll take it to an independent shop (Luxury Motorworks). Unless someone here can solve it first

mrblister

Steve is the go to man at Luxury Motor works He knows our sc430 inside and out

Harold57

The roof action being intermittent tells me that there is a contact failure going on somewhere most likely. Most likely it would be a sensor rather than a switch (though the sensor could actually be a switch). It could also be a wire with a loose or dirty connection.

So it is probably a $2 component causing you all this grief. Unfortunately, I couldn't tell you which one that is.

JohnnyCake

Was she able to reproduce the problem at the dealership? If memory serves me correctly, only the last operation is stored. So you have to have the malfunction while the tool is connected.

I remember going to the dealer with Habious and we ran into the same thing. We dropped the car off for an hour, went to the shooting range, came back and they said, "Gee, no problem, no code." They wouldn't let us in the service area (insurance rules) but they did bring the tester and the car out to the parking lot and we sat there and ran the top until it malfunctioned and we got the code we needed.

Intermittent problems are a PITA.

P.S. Will try your click / lights dim thing and see whether that is the same on a car that does not have the problem.

P.P.S. My guess is that the ECU is AOK, but at $75 its not a bad thing to have an extra. My guess is that a switch/sensor somewhere is giving the ECU bad data.

editordz

They reproduced the problem, but were either unable or unwilling to give out the code. I wasn't personally there, so I let it go. They cleaned out some debris and lubed it. This was a bit over a week ago, and the top has only failed to open once since then. So for now, I'm not going to worry about it further. It doesn't occur frequently enough right now to easily diagnose. Hopefully it'll stay good!


TRUTH!

I'm curious, did you try it, and what were the results?