Drivers Door Control Problem - Help Please!

[johnatg]

Help, please! My IS250 (2006) insists that the front rh door is open when it's not.

On Sunday morning, the car was well frozen up, but it opened OK when I touched the door handle. But the mirrors didn't fold out (I have a PO40 fitted). I was able to fold them out with the switch - it's possible that the mirrors were frozen at first but the engine had been running for a couple of minutes whilst I was clearing the screen before I noticed and by then the mirror heaters had kicked in and the ice round the mirror pivots had melted.

Thinking nothing of it I embarked on a journey of approx 70 miles and parked the car. During the journey the 'front RH door open' sign came up on the dash a couple of times. Thinking that the door switch had got a bit sticky, I opened the door and slammed it shut each time and it cleared. But at the end of the journey the car wouldn't lock with the door handle button (nor with the remote). I did eventually lock it with the internal thingy and exited the car through the passenger side. I locked the car up with the remote.

I then went on a short journey and had the same performance when I parked. Then another short journey and this time at the end the car simply would not lock at all. Soon I drove home - all the while with the red light flashing and the sign saying front rh door open (and bleeps as well with the sign 'move to P range' when I slowed nearly to a stop). When I finally parked at home the car would not lock even with the mechanical key. Eventually I disconnected the Battery and it then did lock (manually on each door).

Now - door lock works from the switch on the drivers door - all doors lock (including the RH front door) but then instantly unlock (but the drivers door stays locked). The drivers door window works from the door switch but none of the other windows work from the rh door switch. They do work from their own switches on each door. Drivers door lock works from the switch but not the handle or remote, but it won't unlock. If the Battery is connected the other doors won't stay locked.

I can't find any fuses blown and I've checked the rh door sensor switch - it is fine (and I think never was a problem).

Any ideas anyone? The circuit diagrams part of my workshop manual doesn't work - does anyone have a circuit diagram of the drivers door electrics and controller?

[is200 Newbie]

I would check the P40 install (even thou it has probably been installed for a while) - make sure grounding connection has not come loose.

Also - only recently (last week) I had noticed when I had the passengers side window open (only that one and only about an inch or so) I had my hand resting by the memory buttons on the door card while travelling on a motorway and there was a big draft coming from around the memory button area. When I closed the passenger window the draft stopped.

It could have only been coming through the door through the gap in the door jamb. With all the cold and wet weather then I would check if its wet within the door at the P40 location.

I also had frozen mirrors but they opened ok when unlocking the car

[Ashpoint]

I have had issues responding to this thread and don't want folk to feel that I am hiding any criticism of the Po-40 kit.

I can (and have) attach the text that I have sent to John.

I the meantime I will research why I couldn't paste my reply here.

Michael

JC_Jan7.pdf

[normski2]

Top reply Michael.

That deserves a pat on the back.

[Ashpoint]

My problem is I have a medical condition that makes it hard for me to type extensive messages - so I dictate (Dragon Dictation V13) into most PC applications (Outlok, Word, Excel, etc.)

Because Dragon can't cope with taking dictation into the web nature of the forum, my message is created in a companion dictation box. When I'm done, Dragon is "supposed" to paste the content of the dictation box into the forum.

It usually works well but not in the case of most Forums.

I'm going to open a "ticket" with Dragon support and hope they will resolve the problem.

[Ashpoint]

I know this is off subject but please excuse my indulgence.

For those of you who are using Dragon Dictate and have followed my prior reply. I can now tell you that the solution is simple – don't use Internet Explorer. I'm now using Firefox - problem resolved!

I'm dictating this into the dictation box and when completed, I will press the "transfer" button and the dictation I've prepared should go into the web page. Only one minor problem, and that is that the formatting is a mess (no paragraphs or line feeds) but that's a small price to pay.

Now in regards to the John's problem at the moment, it seems that it's been so cold where John is located that he's put on hold any further investigations till he can get out to the car. (I sitting here in Sydney with 28c weather <grin>)

I am ready to supply him with a replacement Po-40 Folding Mirror Kit pending his request. At the moment he doubts if the Po-40 Folding Mirror Kit is the problem.

Obviously he and I will keep you informed.

Michael

[johnatg]

Hi guys

Oh shame! I've admitted defeat here.

Been having a hard think about what can be wrong. The door sensor switch (it simply carries a signal to earth when the door is open) works fine. The window switches in the Multiplex Network Master Switch (the switch panel in the door) don't work, but the window switches in the individual doors do work. Central locking doesn't work (as far as I can tell - if I lock with the MNMS switch they all lock, then instantly unlock - except the drivers door - the only way to lock and unlock the drivers door is to use the handle catch or the mechanical key. The mirror fold switch in the MNMS panel works OK. I rather think that all these switches feed in to one unit. Everything is clean and dry, both in the door (PO-40 location) and in the driver's footwell and the side walls.

And there's a rather unpleasant smell of failed electronic component in the driver's footwell. So maybe a component in the double door lock ecu has failed (I know where it is theoretically, but I'm damned if I can find it. let alone get to it).

The faults manifested themselves gradually and progressively during the day on Sunday. Started off minor and intermittent - now I've got a load of hard faults.

I'm so convinced that it isn't the PO-40 that I have not removed it, but I've booked the car in to Lexus Stockport next Tuesday to get some diagnosis with the Intelligent Tester. Apparently it's £82.50 for initial diagnosis. Better start raising some (a lot!) of cash! :(

Many thanks to Michael - he called me and we had a discussion about it. Brilliant!

I'll keep you informed.......

[normski2]

Hope you get to the bottom of this little snag matey.

Looks like you're onto it if you can smell something has burned out.

Had a issue in my old is200 with the illuminated door cills playing up. Detected a strange burnt plastic/electrical smell...turned out to be the transformer under the cover in the footwell.

Hope its not too costly a fix!!

[toffee_pie]

ouch, hope its not too expensive.

I soldered my po40 connections, and used heat shrink, works perfect still.

top marks to Mike for a fast response.

[johnatg]

Hi guys

Well, it's fixed. It took Lexus Stockport most of Tuesday and Wednesday morning to find the problem and do the repairs. It involved a pretty comprehensive strip down of the dash and driver's door. The Intelligent tester wasn't much help, but they did eventually trace the fault to this box (known as Box, Junction - L82730-53130)

http://tinyurl.com/qympzxa

No sign of damage on the outside (eg to terminals)

http://tinyurl.com/n7kpf2a

http://tinyurl.com/pxkoq6y

It was hard to open and they broke a tab off in the process (see first pic of terminals above, near top right) - but they were sure the problem lay inside.

They found this:

http://tinyurl.com/o34wkh2

Close up here:

http://tinyurl.com/qfdn24j

Any electronics experts willing to hazard a guess as to where that started?

They threw in a free tin of sweets, air freshener, key ring, wash and valet and a cup of coffee. So all in all quite a bargain really at £1040! About £600 (after discount...) for the box and the rest labour - and that should have been twice as much.

I could have done without that just after Christmas!

Can't really fault Lexus Stockport - they kept me informed as they went along. They've never seen this before.

These Lexus showrooms are a new experience for me. All fancy decor and soft lights - and very quiet! More like an upmarket intimate night club before opening time - waiting for the clientele! (Now there's a business idea, Mr Toyoda!)

They did offer me the two year warranty for £795 - but with the obligatory servicing etc I still reckon I'm quids in without it over the past three years. Makes you wonder though!

[Ashpoint]

Thank you John for a comprehensive report. That is one VERY big mess albeit with an "ouch" price. I believe that you would acquire a fairly sizable warranty on that component to protect you in case the actual cause was outside the module.

These days when one deals with electronic components the damage can be microscopic and indiscernible. Your technicians at the dealership were guided by the (presumably) rich smell of roasted electronic components.

I have sent an email to a friend who may be able to find information about the damaged component. I've asked him if he could find the purpose of the module and perhaps guess the cause of the damage. It would be interesting if readers of this thread have some ability to also throw light on the component.

I was interested in your comments regarding the atmosphere at the dealership and when I visit the UK (late June) I'm going to make it my business to visit a Lexus dealership and compare what we have here in Australia. My dealership (Lexus Chatswood) always makes me very welcome if I happened to drop by with a query. The car is always washed before being handed back to me (together with the small bag of chocolates). In the past they delivered me a loan car while mine was off the road. They have a pristine waiting room complete with nibblies, fruit, sandwiches and liquid refreshments. They really are customer focused and competitive even against other dealers!

Cheers,

Michael

[toffee_pie]

is that part on the door? from what I can see it could be due to water ingress, a short circuit of sorts? that part that is at the epicentre of the burn out could be a diode or a capacitor, perhaps?

[johnatg]

The unit is fitted behind the dash on the driver's side. The technician was pretty apprehensive about just plugging in a new unit and carried out extensive checks on the wiring to check for water ingress, shorts, chafes, etc. Nothing was found - all wiring in the dash and doors is clean and dry and in perfect condition and it all checked out. They also checked the main body ecu which is fitted behind the left hand end of the dash

The new unit was therefore fitted - it works perfectly. The dealers were happy to leave the PO-40 unit plugged in and connected - they couldn't see that it could have any effect on the issue - and I don't think it did either. So I'm happy to give that a clean bill of health.

There was absolutely no indication of any problem outside the junction box (except for the smell - and even that was quite contained). The conclusion at least for now must be that it was caused by a spontaneous component failure - if a capacitor starts conducting or a resistor starts passing more current than it should all hell can break loose. Hard to tell which component failed first - that IC (or resistor block?) with a hole blown in it looks pretty bad but is it chicken or egg?

[toffee_pie]

that part that is burned out, the main component looks to be a capacitor or some other relatively high footprint count smd component, it could also be a diode of sorts.

I have a masters in Electronics myself so these things are interesting to me/

but i need to draw the line when they are just black blobs...

[toffee_pie]

if you get meths can you get a toothbrush to clean that pcb and reveal component designators?

[johnatg]

I tried to clean it but it wasn't very succesful. Clearly the majority of components on the board are resistors and capacitors with a few transistors and diodes. The big blown up component is a diode, although I couldn't see a label on it. It is the same type of component as the one just along from it - see the overall view of the board referenced above - there are three diodes in a row, from top centre (D027) then to the right - one you can't see (under the board?) - D029, then the blown up one. That came off the board as soon as I touched it with the toothbrush and the board is too badly burnt to read the reference.

The heat from that component had damaged the case - if you look at the first pic the 'dimple' on the case (near bottom right) is in fact heat damage.

As the symptoms developed gradually, clealy the whole shebang didn't go bang in one go - the damage spread gradually. But who knows when it started - maybe quite a while ago? - before any symptoms showed up?

Don't know if that gets us any further?

[is200 Newbie]

Hi John - Have you ever had the windscreen replaced

Looking at the board it looks a bit like there is a liquid stain and the screws untouched by the heat look like they are a bit corroded

[johnatg]

Total catastrophe!

I went out to the car last night - it was well iced up, but I touched the drivers door handle - it didn't unlock. I just thought it was too covered in ice so went round to the passenger side and it opened by touching that handle. I started it and went round scraping ice. When I got back in it was showing 'trunk open' and 'rh front door'. I haven't actually opened the boot since before this all went wrong the first time. (The boor does still open by touching the button).

It will be back in to Lexus on Monday morning............

Noo bie - the windscreen has been replaced (before I got the car three years ago) but there is absolutely no sign of water ingress anywhere. I can see what you mean from the picture, but I think that's just photo efects - the screws are clean and bright and the shades in the board are just copper under the green lacquer. And it certainly isn't wet this time.

[is200 Newbie]

Hi John .... There was an issue with replacement windscreens in that they were not being sealed correctly on the is200 and letting water in behind the dash and with Lexus's track record of resolving ongoing issues from model to model (such as brakes etc...) it may be worth a looksee just to see if any noticeable water marks - am only asking because this is probably the first time this problem has been presented on the forum and from a car that has has a windscreen replacement....

Clutching at straws ...

Good luck with Lexus !! Are you closer to the Cheshire Oaks Lexus branch?

[johnatg]

The replacement screen is a Pilkington one. I've inspected behind the dash pretty carefully (had quite a bit of it out myself) and Lexus did a pretty comprehensive strip of the dash last week - absolutely no sign of problems.

The problem has to be with the handle sensing or unlocking functions in the drivers door - everything else still works but the driver's door won't unlock once it's locked. (You can lock the door from the panel switch but not unlock it - all the other doors unlock from the switch) And that takes out things like the window switch functions from the driver's door (only) and the door open sensor circuit.

The fault has to be outside the junction box - it's a substantial design fault that such a thing can cause excess current to flow in the junction box. Something seriously lacking in circuit protection.

I'm in Alderley Edge so Lexus Stockport is much more convenient (and the only really viable choice).

[toffee_pie]

sorry to hear that, are you sure its not the PO40? might be worth taking that off, i am pretty sure that is what Lexus will do also to rule it out.

That green gunk stuff on the PCB is probably epoxy or resin of sort used on screws, I see it often.

[Ashpoint]

Yes, I agree that Lexus will like to rule out any situation where the Po-40 Folding Mirror Kit could be involved. John however, did replace the Po-40 control module with a fresh one without any difference in the behaviour of the car.

I remain confident that the Po-40 is not involved.

Removing the Po-40 would involve rejoining three cut wires and severing the merged leads off 4 others.

John, if as I expect the Po-40 to be be proven benign, I would then replace the Po-40 harness with the T-quick harness that you were supposed to have used in the first place (but didn't because of a miss-read of the installation manual).

I agree that the fault must lie outside the junction box and wonder what part is played by the extreme cold preventing the mirror motors from deploying. Then, possibly passing back the strain on the motor(s) in the form of an overload to the circuitry in the junction box.

[it is possible to unlock the car but leave the mirrors folded by actioning <Unlock>+<Lock> rapidly from your key fob]

It will be interesting to see the result of John's next visit to the Lexus dealer.

[johnatg]

I have removed the PO-40 this pm so now the wiring is effectively standard (with some joins!). The problem is of course still there because the junction box has been destroyed - again.

I don't think it was actually the cold which caused the mirrors not to deploy - it was probably because of the problem in the first place. They did deploy easily with the switch on the door panel. The touch communication system in the door handle seems to be the first thing to go. (Eg central locking doesn't work (lock and unlock) from that (or the remote) but it does work from the internal switch (although the driver's door doesn't unlock)). The switch panel window switches don't work either.

[toffee_pie]

indeed, i hope you agree a good rate with the lexus techs.

[is200 Newbie]

Did you have any indication of any problems before this happened ?