LED Turn Signal Issue

#1
Hi all,

So i bought front and back LED turn signals (part# 7443-A45-T) from Superbrightled.com. After installing them, they blink really fast. After doing a bit of searching on google, there's an explanation on superbrightled.com that says, and i quote, "This happens because your new LED bulbs draw such little power and your turn signal relay sees the bulbs as being out"

They suggest the easiest way is to get an LED flasher module (see the image below) from superbrightled. It's available on their site for 12$ and it's for new toyota models, part# CF18-08.

So I went home and tried to look for the stock flasher module under the driver dash. After looking for like an hour, I give up. I have no clue where it is. Does anyone know where the stock flasher is in the car so i can replace it? Anyone has wiring schematic for the Toyota Corolla 2014? The manuals that come with the car doesn't mention anything about the flasher module.

Thanks!

LED flasher module from superbrightled

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#2
Sure sounds like you need a repair manual for your Corolla.

A heads up; call your State police and make sure the bulbs you've installed are legal. In many states they are not. A ticket can be very expensive.
 
#3
They generally are located on the interior fuse box or around there. If it isn't there, then I'd have no idea where they stuck it. I'll try to treasure hunt for it and see if I can snag a picture of it.
 
#6
Did a little research. Looks like it is behind the driver side kick panel.
I looked there too. IT's not there. I looked everywhere already. So i went to Toyota Technical Information System (TIS) and paid 15$ for 2-day access. I searched for "turn signal" for Corolla 2014 and all I saw was a wiring diagram.



There's no such thing as a flasher module in the 2014 model. But if you look for the flasher module for earlier corolla models, it's there.

So if you really want to use LED signal bulbs on your 2014 Corolla, you will have to install load resistors which I won't do because it's not pretty. The resistor hangs out in the open and put out a lot of heat. Not a good idea.
 
#7
We need CANBUS specific LEDs then.

EDIT: Nevermind on the CANBUS ... just use a load resistor. The ones on superbrightleds.com are shielded and they are 25 ohm wired in parallel, so they won't dissipate that much heat.

P = V^2 / R, so you're looking at 8 watts of power at 14.2 V. That's nothing.
 
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#8
Just make sure you get the 25 ohm and not the 6 ohm, the 6 ohm WILL heat up pretty good. (The 25 ohm will get about as hot as a dome light. They get hot but nothing crazy. The 6 ohm one is approaching headlamp heat, which would definitely be bad).

Another thing you could do is hold it while a friend activates the turn signal, and if it gets hot enough to make you nervous, mount it using a piece of metal (you can bolt the resistor to the piece of metal no problem), then use double sided tape to affix it somewhere away from other stuff (don't mount it directly to any painted surface).
 
#9
Do us a favor, search "flasher" or "turn signal flasher" and see if anything pops up. Behind the trim panel where the power mirror switch is, is another possible location for the flasher. It is just weird that they would completely abandon a separate flasher and attempt to integrate it elsewhere.

I may give Toyota a call tomorrow and see if I can get a mechanic to let me know the location is or confirm that flashers are no longer used.

I hope I am not stuck using load resistors. The whole point of going LED is for brightness, instant on, and nergy saving (alternator working harder = more burned fuel... Energy isn't free)
 
#10
Do us a favor, search "flasher" or "turn signal flasher" and see if anything pops up. Behind the trim panel where the power mirror switch is, is another possible location for the flasher. It is just weird that they would completely abandon a separate flasher and attempt to integrate it elsewhere.

I may give Toyota a call tomorrow and see if I can get a mechanic to let me know the location is or confirm that flashers are no longer used.

I hope I am not stuck using load resistors. The whole point of going LED is for brightness, instant on, and nergy saving (alternator working harder = more burned fuel... Energy isn't free)
Donabed Kopoian, thanks for your input. I'm hesitant about the load resistor but if you decide to go that route, can you come back and give your input? Once you've done it, i might think about doing it. I really like LED all around.

Yes, I look for all possible search words include what you've mention, nothing comes up. No flasher module. There's a table of contents and i've looked up and down many times.

here's the screenshot of the contents:


You won't find flasher module anywhere. Everything is integrated to their circuitry. I'm pretty sure of that.
 
#12
Alright, and I'm guessing that the Combination Meter Assembly isn't somewhere in the dash? You can modify a resistor in flashers (and probably this device) that changes the current threshold to trigger rapid flash. But just the sound of the part suggests that it does flashers, as well as other things...
 
#13
That sucks. Maybe someone will find a hack that doesn't involve load resistors. The ricer flash is annoying.

There really isn't a "hack" to fix that. Either get the right fuse, bulb wattage, or use resistors. I am an electric engineer who designs my own schematics and such and trust me when I tell you this: There really is no way around the ricer flash except the 3 listed methods.
 
#14
There really isn't a "hack" to fix that. Either get the right fuse, bulb wattage, or use resistors. I am an electric engineer who designs my own schematics and such and trust me when I tell you this: There really is no way around the ricer flash except the 3 listed methods.
I'm a computer science major. An electrical circuit that detects bulb outages compares a load to a lower load equivalent. If the load is higher than the eqivalent, normal flash, if it is at or lower, rapid flash.

And LED flasher is essentially a modified stock flasher, with the resistor in the stock flasher pulled out and replaced with a lower ohm resistor in the comparator circuit. There probably is a way to do this in the circuit for a 2014 Corolla, but without being able to see the Combination Meter Assembly (i.e. their new version of a flasher), then there is no way I can look at it and figure out which one needs to be changed. It is also possible that this is controlled by a computer now, and can be disabled.

Plus, I'm into tinkering and this is something new, so it'd be fun, provided that I don't break anything anyway.

Yeah, load resistors are easier ... but it defeats the purpose of LED in the first place (lower current draw).
 
#15
Donabed Kopoian, thanks for your input. I'm hesitant about the load resistor but if you decide to go that route, can you come back and give your input? Once you've done it, i might think about doing it. I really like LED all around.

Yes, I look for all possible search words include what you've mention, nothing comes up. No flasher module. There's a table of contents and i've looked up and down many times.

here's the screenshot of the contents:


You won't find flasher module anywhere. Everything is integrated to their circuitry. I'm pretty sure of that.
I went ahead and got a 2-day. Turns out the Combination Meter Assembly is another term for the Instrument Cluster Assembly. There may be a setting to disable the rapid flash that the dealer can perform. I'm going to dig and see what else I can find.
 
#17
Alright, this is my plan

1. When I install LEDs, deal with the hyper-flash without load resistors.
2. Wait for a junkyard to get a wrecked 2014 Corolla. Idiots are everywhere so it shouldn't take long.
3. Find a wrecked S that I can pull the Combination Meter Assembly From
4. Experiment on that one, and not mine (this guy ties into everything, including the smart key system, so changing something has the potential to disable the car, and like I said, probably well over $2k for that part since it isn't just a basic instrument cluster).

I saved snapshots of the pins that are in the turn signal circuit. With that, and my general knowledge of electronics, I should be able to find a way to eliminate the hyper-flash with LEDs. When I start the experiment, I'll post a thread, but it may be a while before that day comes.
 
#18
Alright, this is my plan

1. When I install LEDs, deal with the hyper-flash without load resistors.
2. Wait for a junkyard to get a wrecked 2014 Corolla. Idiots are everywhere so it shouldn't take long.
3. Find a wrecked S that I can pull the Combination Meter Assembly From
4. Experiment on that one, and not mine (this guy ties into everything, including the smart key system, so changing something has the potential to disable the car, and like I said, probably well over $2k for that part since it isn't just a basic instrument cluster).

I saved snapshots of the pins that are in the turn signal circuit. With that, and my general knowledge of electronics, I should be able to find a way to eliminate the hyper-flash with LEDs. When I start the experiment, I'll post a thread, but it may be a while before that day comes.
Sounds like a good plan. When you get to it, please post the result.
 
#20
Resistor info for older Corollas: http://www.toyotanation.com/forum/3...um/371389-diy-stock-led-turn-signal-swap.html

Alright, this is my plan

1. When I install LEDs, deal with the hyper-flash without load resistors.
2. Wait for a junkyard to get a wrecked 2014 Corolla. Idiots are everywhere so it shouldn't take long.
3. Find a wrecked S that I can pull the Combination Meter Assembly From
4. Experiment on that one, and not mine (this guy ties into everything, including the smart key system, so changing something has the potential to disable the car, and like I said, probably well over $2k for that part since it isn't just a basic instrument cluster).

I saved snapshots of the pins that are in the turn signal circuit. With that, and my general knowledge of electronics, I should be able to find a way to eliminate the hyper-flash with LEDs. When I start the experiment, I'll post a thread, but it may be a while before that day comes.
Lots of modern cars have gotten rid of the flasher assembly (Ford Focus, Hyundai Elantra, Kia Rio/Forte), off the top of my head.

Normally, they integrate the flasher logic into the Body Control module, but Toyota MIGHT have put it into the cluster assembly - or the part of the schematic showing the cluster assembly MIGHT just be for the turn signal bulbs in the cluster itself (the indicators).

The owners manual says you can customize how many times the lights flash for a lane change, so that might be a reason for using logic rather than a flasher module to control them.

Anyway - basically, there are four options for these cars:

  • Live with non-LED turn signals - Probably the best option.
  • Use load resistors.
  • Modify the circuitry, but be aware, you are going to have to figure out which component contains the code, which chip on that component contains the code, figure out a way to extract the code from the chip (it might be encrypted also), figure out what lines in the code you need to change (without changing any other coded functions), figure out how to re-burn the new code to the chip and replace the chip, and re-install the component. Keep in mind also that this will void any warranty on the modified part (either the instrument cluster or the BCM, not sure), and any failure of another part that might have been caused by your modified code would also not be warrantied.
  • I haven't tried this, but it might be possible to go "Old School" with this. - I.e. look up a schematic for a car with a standard flasher - I attached the Hyundai Accent info (but it's pretty useless scaled to 374x280). Modify the wiring so that the outputs of the turn signal switch and the outputs of the hazard switch go to a traditional (in this case electronic - http://www.superbrightleds.com/more...rs/ep27l-led-bulb-electronic-flasher/784/838/) flasher and from there to your turn signals and instrument cluster indicators. You would have to re-wire the turn signals and instrument cluster, and I think you would lose the "lane change flash" feature, but it should work without resistors and without modifying code. (But I haven't verified it and will probably stick with option 1 above (non-LED turn signals).

That said - I do wish you luck and hope you figure out a solution and look forward to reading your results.
 

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#21
Even though the logic for the turn signal assembly is driven by an EEPROM chip, there is more than likely still going to be a shunt resistor for a comparator circuit that can be replaced.

Corollas have two possible turn signal current draws based on whether or not you have the integrated side mirror signals. It would be easier and cheaper for Toyota to use the same circuitry and simply change the shunt resistor versus the costs of making circuitry sensitive enough that would allow the current to run through a microchip to be properly processed by code. Computers are driven by boolean logic, so the code would be as simple as

if (getCurrent(ts) >= (getCurrent(comp) * 100))
setFlashRate(50);
else
setFlashRate(200);

That's what I'm hoping anyway. It would make the most sense since making a comparator circuit that could run through an EEPROM requires a step down of the current that demands very sensitive and expensive instruments, the components multimeters use.

Assuming Toyota went this route, then the advantage would be that the same circuit could be used in all vehicles, and that the same code used and a global variable only needs to be changed. This would suggest that Toyota mechanics can modify this number, as putting the number in the code itself is against programming practices and means that code must be modified and recompiled if an error happens instead of simply changing a parameter.

I'm going to check car-part.com and see if there are any wrecked 2014s out there that I can pull from. There should be a few by now...

I'll also call Toyota to see if they can change it, but this is unlikely.
 
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#22
WOO! Car-Part.com has one listed for $200. Just called them and asked what it would cost to ship it to California and to make sure it is the multi-information display version (it's from an S so it ought to be). Looks like I'll be able to start this experiment sooner than I initially thought.

Thanks for that website Scott.

The advantage to doing it this way (instead of using load resistors) is that you can pick the resistor that will have the correct flash and actually hyperflash if you lose an LED bulb. If you use load resistors and an LED goes out, the load resistor may draw enough current to sucker the computer into thinking all is well, and you'd be none the wiser to think otherwise.

First, I need to call Toyota and actually make sure that this cannot be changed or disabled, because if they can change the number of flashes for the lane change, it is possible (unlikely, but possible) that they can change the value for when hyperflash begins as I mentioned above.
 
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#23
I don't know about Toyota, but keep in mind that a LOT of cars (Ford, Dodge, Kia) store the mileage in the instrument cluster.

If you car has 5K miles on it and the new cluster has 8K mile, you can just wait three months to do the permanent install, but if the new cluster has 5K miles and your car has 8K, you would have to get the new cluster reprogrammed.

Also - some cars require a proxi-alignment to ensure the options on the car and cluster match up - not sure about Toyota, though.
 
#26
I believe the Toyota Turn signals are 7440's.

http://www.diodedynamics.com/store/...s/plug-and-play-inline-led-resistor-pair.html

http://www.ebay.com/itm/T20-7440-LE...047677?pt=US_Car_Lighting&hash=item1e8b8943bd

Either of these should stop the hyperflashing without having to splice any of the OEM wires.

I personally like your idea and on the other hand, likely wouldn't bother with swapping the turn signal bulbs for LED's, but for someone looking for a simple and (relatively) inexpensive solution ...
 
#28
I would be really curious to know how warm those ebay or diodedynamics spliceless plug-n-play resistors get.

Just throwing it out there, maybe some stick-on heatsinks would also help some of the issue. Probably dependent on how thermally-conductive the housings are, unless you want to crack them open.

(obviously these are pretty small, but just for demonstration)
http://www.newegg.com/Product/Product.aspx?Item=9SIA3TR18A6835

EDIT: Total resurrection. I've been looking into going LED everywhere, so wondering where this ended up.
 
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#29
I never posted back (could have sworn I did). It isn't possible for the dealership to change the threshold and they wanted $100+ to install the load resistors.

I'm going to pull my cluster out in October since I am off from school, and probe around and see what I can find.

Those resistors do get pretty warm. You wouldn't want to mount them on anything other than metal, but I don't want to use load resistors.
 
#30
The load resistors probably don't get that hot for turn signals.

I would need them for the brake lights for the Ford Focus (disables cruise control) and those would want to be mounted to metal.
 
#31
They probably don't, but why chance it? Also depends on how much current the load resistor can handle. You pay for what you get.

Yeah, I'm glad that Toyota doesn't disable cruise with the LED tail/brake lights.
 
#32
I've never dealt with load resistors. I have seen other threads where the turn signal ones were zip-tied to the wire harness with no issues.

Not saying it's a good idea, but ...
 
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