Hyper Flash Turn Signals

Karter2026

Goblin Guru
So has anyone else had any luck with installing the resistors for the turn flash speed? I have tried with no luck I get the same speed no mater what I try.

I understand the whole resistance being less with the LED but I do have incandescent turns next to my head lamps, I have the LED mirror turns, and the led STT in the back. Am I missing something? I have even tried 2 of the load resistors on each side with no luck.
IMG_20200406_145215.jpg
 

Briann1177

Goblin Guru
Could you make/purchase a rheostat? That way you can tweak and see if there is a particular resistance where it stops. After that you could find a regular resistor of a similar value.
 
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Karter2026

Goblin Guru
Yep, that should have done it? Did the resistor get hot?
It slowly got warm not hot. I even put a 1157 bulb in line with the resistor still the same speed. it did get hot with this. No change in flash speed.

I couldn't get my TC to not hyperflash - they blink right in the middle of obnoxious and regular so I just gave up and moved on.
That is exactly where I am. I would like them to be about 10-15 flashes per min slower than they are.
 

ctuinstra

Goblin Guru
It slowly got warm not hot. I even put a 1157 bulb in line with the resistor still the same speed. it did get hot with this. No change in flash speed.


That is exactly where I am. I would like them to be about 10-15 flashes per min slower than they are.
If you put the proper bulb in line and it still did it. The problem has to be elsewhere. Can you temporarily wire up a 1157 in front and rear and see if you are still getting it?
 

Desert Sasqwatch

Goblin Guru
Maybe try one of these? The eBay link may not be the correct part number, but there are several different ones for sale of like pricing.
 

Karter2026

Goblin Guru
If you put the proper bulb in line and it still did it. The problem has to be elsewhere. Can you temporarily wire up a 1157 in front and rear and see if you are still getting it?
I will Try that today. I think I did that before. I can't remember.

Maybe try one of these? The eBay link may not be the correct part number, but there are several different ones for sale of like pricing.
These will not work for our cars. the flasher is built in to the BCM.

The hazard's are fine just the turns.
 

Karter2026

Goblin Guru
Update I started testing today with a 1157 in line with the LED light in the rear and one 1157 in line with the front bulbs. Same result.

Did some more thinking Put the resistor in the rear and left the 1157 in the front. No difference.

Aggravated and ready for the fire next!

I put a resistor in the front and rear. Bingo normal turn signals. I guess it will be time to order 2 more resistors. Does anyone think that will cause an issue. I don't
 

bradr

Well-Known Member
Update I started testing today with a 1157 in line with the LED light in the rear and one 1157 in line with the front bulbs. Same result.

Did some more thinking Put the resistor in the rear and left the 1157 in the front. No difference.

Aggravated and ready for the fire next!

I put a resistor in the front and rear. Bingo normal turn signals. I guess it will be time to order 2 more resistors. Does anyone think that will cause an issue. I don't
The turn signals on the Cobalt are all isolated (each corner its own circuit). This is for several reasons including the ability to light one corner at a time for the TPMS learning process. As a result, each will likely need a resistor as you found.
 

Karter2026

Goblin Guru
The turn signals on the Cobalt are all isolated (each corner its own circuit). This is for several reasons including the ability to light one corner at a time for the TPMS learning process. As a result, each will likely need a resistor as you found.
I was hoping that our resident electrical wizard would chime in thanks @bradr .

Now that you point that out it makes much more sense to me. So the older Cobalts without TPMS should be able to only need one resistor.
 

bradr

Well-Known Member
I was hoping that our resident electrical wizard would chime in thanks @bradr .

Now that you point that out it makes much more sense to me. So the older Cobalts without TPMS should be able to only need one resistor.
I cant say for sure, but the would likely need multiple resistors as well. There was only one basic BCM design for any given model year and it supported all available features. It is just a matter of if the features were enabled or disabled in software. Based on the few diagrams I have, I expect all years would need one resistor per "corner".
 

Karter2026

Goblin Guru
More progress during the stay home order. Here is a bit of a update on the hyper flash issue. A fellow builder shared his solution with me. This worked out pretty good for a location and not having to hide the resistors at each corner.

IMG_20200417_122801.jpg


I ran the ground out to the stud on the side of the battery box.
The LR and RR lights come out of X3 on the red BCM plug. I used about 10-12" of wire total from the resistor.
The LF and RF lights come out of X1 on the BCM (plug under the red one) on this I used 12-14" of wire to the resistor. Some 3M VHB tape to attach the resistors to the aluminum plate and used the same to attach it to the side panel.

IMG_20200417_122807.jpg


All tucked in behind the kick plate.

IMG_20200417_142307.jpg
 
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