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Is200 Auto Mirror Closure


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Duncan - there shouldn't be a problem if you can use a positive feed. It effectively draws no current as it is only a trigger and bearly noticeable - a couple of microamps at the most. Are you powering your timer from it also? If so - don't. power the timer seperately with a perm 12v and only use the microwave feed as the trigger.

Or, try powering the timer with a perm feed and switch your timer onto neg. trigger and try the wire indicated on my diagram above in the pdf. If this works it's got to be the trigger at fault. As a trial, put a 1uf or above capacitor in series with your trigger feed. The ECU may be shutting down the sensor. I can't see it but it will only allow a small pulse to your trigger which is all that you need, rather than a permanent connection to it.

Does this line actually go high when the alarm is set? I've not metered it. There are two lines to the sensor - one is a signal on activation and the other is power. The other line is just green - what state is this in with the alarm set/unset?

Funny, but I was thinking of changing the circuit slightly and connecting to this myself if it only goes high when the alarm is set - it is only a minor change but it means I won't be posting the circuit diagram here until I've done it. (No point in people making up the circuit if I'm going to modify it).

I should be able to do this tomorrow.

I'll keep you all posted!

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Geoffers - regarding the monostable with trigger input, thought that most had this.

Monostables such as the CD4047BC, SN54121 or SN74121 or even LM555 has a trigger input. Some are only positive trigger though, CD... has both I think.

Myabe I am misunderstanding what you meant - could you explain more? What one are you trying to use at moment?

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I was actually thinking of a ready made monostable for people who aren't into electronics that just has a trigger and an output. I'm posting the full circuit diagram, but some will be put off. (Don't mean to sound condescending to anyone here!)

I'm using a ua555 at the moment - the lower power version of the LM555. (Only because it has a perm feed so it's standby current is only a few microamps.)

The 555 only has a negative trigger but I can't find one on the Lexus alarm (other than the one I've used) so I'm going to use the microwave positive feed. As you are probably aware, it's only a case of dropping a tranny in first to switch the pos. trig to a negative one. (And a cap and resistor)

I decided to go for the 555 as space is very limited and you can use a VERY small box. As you are aware, the readily available potting boxes come in set sizes so I wanted to make the circuit as small as poss. I've done it on veroboard so everybody can make one from off the shelf stuff. With the board, switch and relay, it's a bit tight. The physical location in the footwell makes it awkward to say the least.

I know it's only a minor difference, but the other IC's are 14 pin (Or SMD which couldn't really go on vero) so the board would be slightly wider / higher and it makes all the difference.

It's only physical limitations really. If you look at the pdf and where it is mounted, you can see why it's tight. (which is why I used a sloping box. Here's a piccy of the box and circuit inside.

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I was actually thinking of a ready made monostable for people who aren't into electronics that just has a trigger and an output.

Definately for me please Geoffers - Couldn't manage without.

:withstupid:

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certainly looks the biz, nice and compact.

Will have a quick trawl for a better mono then, smallest pin count and leaded being a priority. Though you will still need a few caps and R's to set the time (so to speak!!)

If you want, PM me the schematic, can get a full picture then of whats happening.

Sounds like theres not much too it but a little hard thought.

Access is a big pain down there, at least it will be out of site though. Wonder if we could get a LEXUS switch from their parts dept. to go in a spare slot in dash - maybe one near rear fog bit???

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back again.

How about the Philips ICM7555 which has a much lower supply current, about 80-100uA. Can supply 100mA.

Are you buffering the outputs, seeing as they will effectively drive a cable?

Guess you probably know this site anyway, but have a look through www.farnell.com (redirects to uk1.farnell.com) then click online catalogue, semiconductors, IC's, timers, there are loads there, was thinking about lower power ones and cheap (most about the 50p mark) Then all you need is a couple of caps a resistor and whatever else you had (tranny, relay etc).

Seems most with non-inverting inputs are 14-16 pin. :(

What length of time is the trigger pulse, and what output pulse width do you need?

Its sad really, that I can get so involved in this (what we call a "homer") yet can't be bothered to do my actual work!!

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I was thinking of the complete mono, including R's and C' with just a pot to adjust the time. It's annoying because Maplin used to do one.

We have the circuit to build, it was just to save users adding any componants. All that would be needed is to solder the wires on to it and the relay.

I'm in work now, I'll PM you later.

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Duncan - there shouldn't be a problem if you can use a positive feed. It effectively draws no current as it is only a trigger and bearly noticeable - a couple of microamps at the most. Are you powering your timer from it also? If so - don't. power the timer seperately with a perm 12v and only use the microwave feed as the trigger.

Or, try powering the timer with a perm feed and switch your timer onto neg. trigger and try the wire indicated on my diagram above in the pdf. If this works it's got to be the trigger at fault. As a trial, put a 1uf or above capacitor in series with your trigger feed. The ECU may be shutting down the sensor. I can't see it but it will only allow a small pulse to your trigger which is all that you need, rather than a permanent connection to it.

Does this line actually go high when the alarm is set? I've not metered it. There are two lines to the sensor - one is a signal on activation and the other is power. The other line is just green - what state is this in with the alarm set/unset?

Funny, but I was thinking of changing the circuit slightly and connecting to this myself if it only goes high when the alarm is set - it is only a minor change but it means I won't be posting the circuit diagram here until I've done it. (No point in people making up the circuit if I'm going to modify it).

I should be able to do this tomorrow.

I'll keep you all posted!

Hi Geoffers,

Is the green/brown in your pdf a neg. output from the door locking, or is it from the alarm to the microwave(pos. output).....(didn't have time to check it with the multimeter) ?

I'm using 2x 5 pin relays to do my motor interupt circuit(one relay closes the mirrors and the other opens them again) I did it this way coz i may link both relays to the locking circuit, sothat the mirrors close when locking the car via the key fob, and then open up again when the alarm is switched off.

I have done this in a mock-up on my car and it works great. You do however need to use 2xtimers, one for each relay.

The timers only allow the relays to be active for 4 seconds, which is enough time for the mirrors to close/open.

This means the relays are'nt drawing any current when the cars standing with the alarm on...

PS: I'm not into electronics like yourself, so i havn't "home grown" any circuitry. My two relays are ordinary 12v 5 pin relays available from any car shop at about £3 each, and the adjustable timers i've used are Sigma SIGAC05 which are available from most car security outlets.

FOR ANYONE OUT THERE WHO'S THINKING "WHAT THE F*CKS A CAP/RESISTOR/TRANSISTOR etc.. and for those of us (including myself) who hav'nt a clue about electronics and circuitry IT CAN BE DONE WITH BIG DUMB RELAYS AND A BIT OF WIRE!!!!....

(hats of to you geoffers mate...."YOU DE MAN".....) B)

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The output is actually from the door locking and alarm ECU combined. It is a negative output.

If you connect to the locking circuit, wouldn't the mirrors close if you locked them by the door switch while you're driving? I thought of that method too, but using the deadlock as the trigger (so they wouldn't trigger by locking the doors internally) but there isn't a seperate signal - it's just an extended tone for the deadlock.

I've used a single timer and single relay. Can you draw a small circuit to show me how you've done yours? I'm not familiar with the timers you are using, but my circuit is just a timer and relay - that's all. I've probably just gone into too much detail really.

When using 2 relays rather than a single changeover, isn't there a danger if you have 'sticky contacts'? Wouldn't you be applying pos to ground at the same time?

If you can show me a way of doing it with a couple of relays and wire, I'd really like to see it! Seriously, I would - we can all overlook the obvious sometimes - I just can't picture it or see why Lexus didn't do it if this is the case.

Isn't the sigma an electronic timing circuit just like mine? I would like to see them - are they on any website? Do you have any details or anything? I'll call round a few places tomorrow and have a look for them. I'm sure we could use them as it will be exactly the same as my timing circuit but ready made. (which is what I'm looking for to save people making them). How much are they?

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Managed to source Timer relays perfect for the job.WWW.directed.com(Clifford product).

Part number 528T PULSE TIMER RELAY.

I'm using two of these timer relays. One to close the mirrors on locking the doors, and the other to open them up again when the doors are unlocked. This is fully functional and has been working fine on my car for over a week now without any side effects.

The timers are switched though a relay, triggered from the ignition key sothat if you want to lock/unlock the doors while your driving, it won't effect the mirrors.

I've also fitted a "valet " switch which cuts the earth supply to the timers, sothat the mirror functin can be switched off if need be(servicing).

The switch of the timer relays is done via a "two way" micro switch linked to the lock/unlock button inside the drivers door. I did it this way to prevent any unforseable problems arrising with the central locking(warranty on the locking system is still valid) as no locking wires have been touched.

Will post a diagram of my system for all to see, when I get chance to draw one up...

THANKS FOR YOUR INPUT GUYS :D

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Cheers Duncan, Good way of doing it!

I was trying to keep the complexity down and wiring, so I've done mine slightly differently in that it closes the mirrors on alarm set, and opens them again on ignition. I see why you have two timers/relay now. Using a single changeover relay and single timer just restores the mirror circuit to it's normal state when the ignition is back on. (You can disable the circuit as well of course.)

I've found a source for the timers in the UK for about a tenner. I've ordered one in so I'll test it and see how it goes then post it on here.

Everybody now has both options.

Nice one!

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Cheers Duncan, Good way of doing it!

I was trying to keep the complexity down and wiring, so I've done mine slightly differently in that it closes the mirrors on alarm set, and opens them again on ignition. I see why you have two timers/relay now. Using a single changeover relay and single timer just restores the mirror circuit to it's normal state when the ignition is back on. (You can disable the circuit as well of course.)

I've found a source for the timers in the UK for about a tenner. I've ordered one in so I'll test it and see how it goes then post it on here.

Everybody now has both options.

Nice one!

The timers I'm using, can be triggered by a + or - pulse, or by a change of state(from + to - or vice-versa).

Would this help you in developing another way around it? :yawn:

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Yep - I've actually ordered a similar timer to the ones you're using. (Would like the same type but can't seem to source them from the UK)

My latest circuit does both pos+neg, but I wanted something ready built for users who aren't into electronics or just couldn't be bothered building it from scratch. All people will have to do is add a double poll changeover relay, make the connections in the footwell and that's it.

You've done us a favour finding these ready made.

Cheers mate.

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Found a place near me that stocks my timer relays. They can be ordered over the internet, or by giving them a call.

Check out: www.ikelectronics.com

(couldn't find the timers on their website, but have been into the shop and seen them on the shelves)

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Managed to source Timer relays perfect for the job.WWW.directed.com(Clifford product).

Part number 528T PULSE TIMER RELAY.

I'm using two of these timer relays. One to close the mirrors on locking the doors, and the other to open them up again when the doors are unlocked. This is fully functional and has been working fine on my car for over a week now without any side effects.

The timers are switched though a relay, triggered from the ignition key sothat if you want to lock/unlock the doors while your driving, it won't effect the mirrors.

I've also fitted a "valet " switch which cuts the earth supply to the timers, sothat the mirror functin can be switched off if need be(servicing).

The switch of the timer relays is done via a "two way" micro switch linked to the lock/unlock button inside the drivers door. I did it this way to prevent any unforseable problems arrising with the central locking(warranty on the locking system is still valid) as no locking wires have been touched.

Will post a diagram of my system for all to see, when I get chance to draw one up...

THANKS FOR YOUR INPUT GUYS :D

Have now added total window closure, so by pressing the lock button on the ignition key not only locks the doors and sets the alarm, it aso closes the mirrors and windows.

Pressing the un-lock button un-locks the doors, switches the alarm off, and opens the mirrors back up again

Has been on test all weakend with no side affects!!!!... :D

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Fantastic.

That's the next add on to mine - just another relay with a couple more contacts. Do you rely solely on the currrent sensing for the windows or have you put in a microswitch or any other sort of detector? I'm just a bit concerned about the current drain. The current sensors in the windows are that sensitive.

I've not actually timed the windows yet - Have you left it on 4.5 - 5 secs?

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  • 2 weeks later...
Managed to source Timer relays perfect for the job.WWW.directed.com(Clifford product).

Part number 528T PULSE TIMER RELAY.

I'm using two of these timer relays. One to close the mirrors on locking the doors, and the other to open them up again when the doors are unlocked. This is fully functional and has been working fine on my car for over a week now without any side effects.

The timers are switched though a relay, triggered from the ignition key sothat if you want to lock/unlock the doors while your driving, it won't effect the mirrors.

I've also fitted a "valet " switch which cuts the earth supply to the timers, sothat the mirror functin can be switched off if need be(servicing).

The switch of the timer relays is done via a "two way" micro switch linked to the lock/unlock button inside the drivers door. I did it this way to prevent any unforseable problems arrising with the central locking(warranty on the locking system is still valid) as no locking wires have been touched.

Will post a diagram of my system for all to see, when I get chance to draw one up...

THANKS FOR YOUR INPUT GUYS :D

Have now added total window closure, so by pressing the lock button on the ignition key not only locks the doors and sets the alarm, it aso closes the mirrors and windows.

Pressing the un-lock button un-locks the doors, switches the alarm off, and opens the mirrors back up again

Has been on test all weakend with no side affects!!!!... :D

Sunroof has now been added to the closure system. Slide and tilt, both working...

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  • 2 weeks later...

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