One-touch turn signal modification

[revtor]

The optocouplers should only be required for IN_LEFT_INDICATOR and IN_RIGHT_INDICATOR. IN_LEFT and IN_RIGHT don't need any (unless your turn signal lever is different from the BMW E31 one).

Most comfort blinker circuits are time-based, but this one is pulse-based. It will not work unless it senses pulses on the IN_LEFT_INDICATOR and IN_RIGHT_INDICATOR inputs. These are used to count the number of blinks. Thus if you want to test the circuit, you must provide something that gives pulses as if it was a flasher relay. Other comfort blinkers which are time-based work perfectly without these extra signals. But these do not support the full flash as this module does...

[mumtaz]

The optocouplers should only be required for IN_LEFT_INDICATOR and IN_RIGHT_INDICATOR. IN_LEFT and IN_RIGHT don't need any (unless your turn signal lever is different from the BMW E31 one).

Most comfort blinker circuits are time-based, but this one is pulse-based. It will not work unless it senses pulses on the IN_LEFT_INDICATOR and IN_RIGHT_INDICATOR inputs. These are used to count the number of blinks. Thus if you want to test the circuit, you must provide something that gives pulses as if it was a flasher relay. Other comfort blinkers which are time-based work perfectly without these extra signals. But these do not support the full flash as this module does...

I understand the functions. But. I not read this line in your "manual":

"...the OTTS module requires ground level signals from the turn signal lever switch."

And I killed 5 ATtiny2313 to teach myself: "Always read carefully all words"

Other problem, while I use optocouplers. The Vectra B turn signal switch have one pin with +12V. This is shared with high/low beam switch. So thats while I use optocouplers and not rewiring the switch. This car is not have seperated indicators to left and right turn signal, but have two seperated relays the left and right side. So, this is not problem, to connect the module.
Monday I run to buy an other ATtiny2313.

My other project is to build a windshield wiper intervall timer with ATtiny13.

Thanks for Your help.

[revtor]

Oh I see. I thought I made that quite clear in the compatibility listing, but maybe I should hightlight this a bit better... On the other hand, the article was written for the E31. If you have an E31 and follow the article, it can't go wrong. If you have a different car you have to pay attention to the electrical differences - as you just learned. Well, luckily the ATtiny series are rather cheap

I could have made a module that works in virtually all cars (much like the jalt.de modules), but I did not have any commercial interests and the only car I needed the module for was the E31...

Anyway, I'm glad you found the problem and find my circuit useful!

[mumtaz]

Anyway, I'm glad you found the problem and find my circuit useful!

This is not a problem. This is the very best turn signal modul what I find on internet. Just have very small modifications to operate in other cars, not just E31.

Thanks man.

Maybe other AVR->car projects? ;-)

Update: I get a new attiny2313 -> programmed -> testing -> modul working perfectly -> Mumtaz happy.

Thanks again. :-)

[mumtaz]

I wired the modul to my car. But. 1 seconds after power up the module, the LM2931 is burning.

Idea? Heatshink or other regulator?

[revtor]

A heatsink should not be necessary. Mine doesn't even become warm. We are talking micro amps here, not even milliamperes. It's a low-power voltage regulator, so obviously something is drawing too much current. You don't happen to power the relays from the LM2931Z-5, do you? The 2931 should only power the ATtiny2313. It's not capable of driving something that requires real power. The relays are powered directly from the 12 V battery voltage. Check for short circuits to the ground on the output of the 2931.

Do you at any chance have multimeter that can measure capacitances? If so, remove the ATtiny2313 and measure the capacitance between pin 20 (positive terminal) and pin 10 (negative terminal) of the IC socket. It should read 100 µF (give or take 10%). If not, the wiring on the output of the 2931 is wrong.

[mumtaz]

The relays powered directly from battery. I tested the modul funcionality days ago with a simple 12V adapter and working perfect. Just if powered the module in my car the regulator warming up equal to a bbq.

[revtor]

Could you still measure the capacitance as described in my last post? If you multimeter cannot measure capacitances, use the Ohm reading (respect the polarity). The reading will be pretty worthless because of the capacitors, but it should not read anywhre close to 0 ohm. If it is continuously increasing, that's ok.

When you tested the board on a separate 12 V power supply, it worked. So I guess it's safe to assume the problem is not in the module but in a difference in wiring between the test setup and the actual situation... Did you fully test the board in the test setup? Everything worked as expected?

Just wondering... Does the ATtiny2313 still work after frying the 2931?

You can try to replace the 2931 with a heavy duty voltage regulator, but I'm afraid that will only result in the frying of another component. Something is drawing more current than it should. You must find out what.

It's rather difficult for me to diagnose the problem without your car and PCB to perform tests on. If you don't mind blowing another 2931s, you can try trial and error.

1. Put the module in the car but only connect its power (12 V and GND). Reconnect the battery, trun the ignition, or whatever you have to do to get the module powered. Wait a few moments. If nothing bad happens, go to the next step.

2. Connect the outputs (OUT_LEFT and OUT_RIGHT) and retry. If nothing bad happens, disconnect the outputs again and continue with the next step.
3. Connect the flasher relay inputs (IN_LEFT_INDICATOR and IN_RIGHT_INDICATOR) and retry. If nothing bad happens, disconnect the inputs again and continue with the next step.
4. Connect the turn signal lever inputs (IN_LEFT and IN_RIGHT) and retry. If nothing bad happens, disconnect the inputs again and continue with the next step.

5. Connect the outputs (OUT_LEFT and OUT_RIGHT) and retry. If nothing bad happens, next step (leave the outputs connected).
6. Connect the flasher relay inputs (IN_LEFT_INDICATOR and IN_RIGHT_INDICATOR) and retry. If nothing bad happens, next step (leave the inputs connected).
7. Connect the turn signal lever inputs (IN_LEFT and IN_RIGHT) and retry.

8. Well... You shouldn't come this far. One of the above steps should fry the 2931. Which step?

[Lachlan]

Pardon my ignorance, but how does one program the IC? I assume there's some way to hook it to a usb port or something, but I've never done it before.

[revtor]

There are many ways of programming AVR devices. I use the Atmel AVR Dragon - a low-cost programmer and emulator. Great tool while developing. But if you only want to program and not develop/emulate, there are cheaper alternatives - even simple DIY interfaces. But that's a bit beyond the scope of this thread. If you are really interested in starting with programmable logic, head over to sites like avrfreaks.com... The Atmel AVR family is very popular and there are many sites and communities dedicated to it.

[sightseeker]

would be nice if someone did this as a plug and play...for those of us that get lost in the electronics feild..so if its going to be done i'd like to be on the list for one....

[mumtaz]

...

1. Put the module in the car but only connect its power (12 V and GND). Reconnect the battery, trun the ignition, or whatever you have to do to get the module powered. Wait a few moments. If nothing bad happens, go to the next step.

...

I tested the module without Attiny. The 2931 temperature is not change. 29 Celsius. But if I plug in the attiny, the 2931 temperature continuously go up.

And my brain is burning up.

[revtor]

The Opel has a common 12 V on the turn signal switch. What changes did you make to the OTTS circuit diagram to support this?

What I don't understand is that when you test it outside the car, it works fine. But in the car it fries the 2931. There must be a difference!

PS: It's probably a bit late, but I'm currently working on a new version that supports both ground and 12 V level signals on the input and outputs. It's based around a ATtiny24 - just a bit cheaper and the circuit doesn't need all input/outputs of the ATtiny2313.

[mumtaz]

The Opel has a common 12 V on the turn signal switch. What changes did you make to the OTTS circuit diagram to support this?

...

Just two Optocoupler to left and right input.

[revtor]

And by doing so, did you perhaps choose other pins than I did? And if you did, did you perhaps forget to change the source code? And if you changed the source code, did you program an internal pull-up resistor for these pins (void initialize())?

[mumtaz]

And by doing so, did you perhaps choose other pins than I did? And if you did, did you perhaps forget to change the source code? And if you changed the source code, did you program an internal pull-up resistor for these pins (void initialize())?

Nothing more change.

Anyway I changed the 2931 to 7805. The 7805 output to attiny pin20 129mA. And 7805 is very hot. It's not too mutch?

[revtor]

I haven't measured the current myself, but I estimate the current through pin 20 should be in the microamps range when doing nothing and somewhere between 5 and 15 mA when active - depending on what the module is doing (estimation based on values taken from the ATtiny2313 datasheet). So yours is way too much...

The 2931 on my prototype and final module stays cold.

Maybe an idea... keep the 7805 for now since it can deliver enough power. Can you measure which pin(s) draw(s) a large current? The pins to measure are 2 (PD0), 4 (PA1), 9 (PD5), 13 (PB1), 14 (PB2), 15 (PB3), 16 (PB4), 17 (PB5), 18 (PB6), and 19 (PB7).

[mumtaz]

I haven't measured the current myself, but I estimate the current through pin 20 should be in the microamps range when doing nothing and somewhere between 5 and 15 mA when active - depending on what the module is doing (estimation based on values taken from the ATtiny2313 datasheet). So yours is way too much...

The 2931 on my prototype and final module stays cold.

Maybe an idea... keep the 7805 for now since it can deliver enough power. Can you measure which pin(s) draw(s) a large current? The pins to measure are 2 (PD0), 4 (PA1), 9 (PD5), 13 (PB1), 14 (PB2), 15 (PB3), 16 (PB4), 17 (PB5), 18 (PB6), and 19 (PB7).

Ok. I build a simple. 7805, three capacitor. I plug to the attiny, and the 7805 is very hot after 5 sec. I plug to another (clear new) attiny, and stay cold. So. This is the 6th "dead" attiny. Work, but "dead".
I dont know, why, but with new attiny the 7805 stay cold, and the module is working.

[revtor]

Weird... Several people already built the module - even modified - but none had any problems with component failure. I really don't know what caused all your problems, but it seems the new ATtiny fixed it. Luckily the ATtiny2313 isn't that expensive.

Just a thought... Perhaps you should use an ESD wrist strap to avoid damage to sensitive devices like the ATtiny due to static discharges?

[Mr T]

Hello . I just bought the components for "one touch turn...", and 1 question came up, do you have the pcm layout for it? Version 1 , not the one with programmable system. ThAnKs PS keep up the good work .

[revtor]

Hello . I just bought the components for "one touch turn...", and 1 question came up, do you have the pcm layout for it? Version 1 , not the one with programmable system.

I don't have a PCB layout. I started development of the updated OTTS module with programmable logic soon after finishing the first version. But I do have high resolution pictures of my own PCB's top and bottom which you can use to build your own version (on prototyping board). If you're interested, send me your e-mail address in a private message and I'll send the pictures your way.

I'm also thinking about an updated version of the v2 OTTS module. This time with a smaller ATtiny24 and using MOSFETs instead of relays. A module that works with both high level and ground level inputs and outputs. But I don't have much time at the moment, so these plans are postphoned till who-knows-when...

[rcrad6653]

A bit OT Revtor, but is it possible do you think to do a mod of the driver's window switch where it continues all the way down with one touch? TIA

[revtor]

A bit OT Revtor, but is it possible do you think to do a mod of the driver's window switch where it continues all the way down with one touch? TIA

Isn't that how it works right now?

• Soft press on a button: window moves until the button is released
• Hard press on abutton: window goes all the way down or up

The only exception to this is the upward movement of the rear windows. For whatever vague reason the "rear up" buttons don't have two positions.

I guess you mean something like a single press to get all windows down automatically and the same in the opposite direction? I have already been thinking along these lines, but apparantly Martin from 8er.org beat me to it: Fenstersteuermodul FSM (window control module) - sorry only available in German, but Martin speaks English. It's not cheap, but it's a rather complex microcontroller. Martin reverse engineered the bus protocol between the window switch module and the relay/general module. His module just intercepts the data on the bus and recodes it. Very nice approach although he mentions possible timing issues on the bus (does not affect the car - just his module).

A more simple approach would be putting microcontroller outputs "parallel" over the window switches and simulating button presses. But that's a lot of wiring and the board probably will not fit inside the window switch module. Probably involves making holes in it to get the cables in and out. Can't say I like that.

[rcrad6653]

Yes. I said driver's window but meant what you describe. Thanks for the info that it's doable at least.

[Mr T]

I get an error when I try to send private message, but my email is tcew@bastu.net .Thank you very much...