LED to Halogen...error/rapid flash

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I have a basic understanding of automotive electricity but it is certainly not my speciality. Long story short. I have a 2019 Chevy Malibu that needed all new tail lights. They are the newer LED tails. I replaced them with ones off a pre-facelift Malibu which are halogen units. The LED tails cost 5x what the halogen ones cost, which is why I didn’t buy LEDs to replace them.

Issue I’m having now is after a few seconds the turn signal rapid flashes and the car detects the rear turn signal is out. Everything works fine but the computer keeps thinking it’s out.

usually people go halogen to LED not the other way around. Adding a resistor mimics a halogen bulb and all is good.

But what about LED to halogen? Assuming there is now MORE current draw than what the system is set to detect, why would the error message show up? Wouldn’t a dead LED cause it to not complete circuit and cause the warning light? Why would a complete circuit set it off at this point?

I was thinking of throwing in cheap LED bulbs without resistors to see if it does the trick. If that doesn’t work, would swapping the tail light fuse for a higher amp rating be beneficial? Any other possible solutions?
 
I'm not claiming to actually know the answer, but following the resistance issue when going from halogen to LED, I wonder if this is the same problem but in reverse. Something like halogen ----> LED = out of range (low), LED ----> halogen = out of range (high).

The "add a resistor" fix for the halogen to LED issue obviously wouldn't work as it would only serve to compound the problem in this case. If in fact my theory is correct. Which it probably isn't.
 
I have a basic understanding of automotive electricity but it is certainly not my speciality. Long story short. I have a 2019 Chevy Malibu that needed all new tail lights. They are the newer LED tails. I replaced them with ones off a pre-facelift Malibu which are halogen units. The LED tails cost 5x what the halogen ones cost, which is why I didn’t buy LEDs to replace them.

Issue I’m having now is after a few seconds the turn signal rapid flashes and the car detects the rear turn signal is out. Everything works fine but the computer keeps thinking it’s out.

usually people go halogen to LED not the other way around. Adding a resistor mimics a halogen bulb and all is good.

But what about LED to halogen? Assuming there is now MORE current draw than what the system is set to detect, why would the error message show up? Wouldn’t a dead LED cause it to not complete circuit and cause the warning light? Why would a complete circuit set it off at this point?

I was thinking of throwing in cheap LED bulbs without resistors to see if it does the trick. If that doesn’t work, would swapping the tail light fuse for a higher amp rating be beneficial? Any other possible solutions?

The body computer looks for a narrow range of voltages. The higher amp draw increases the voltage that's measured inside the body computer. Maybe the body computer can be coded for halgen lights, otherwise you will need a relay or so.
 
What you discovered about the cost of factory LED lights is going to bite 2nd and 3rd owners as all these LED equipped vehicles age. Maybe the aftermarket will step up. Curious if they both went bad in a 2019 or there was some unintended bodywork involved?
 
The computer(s) are looking for a certain current/voltage. Someone with a scan tool capable of editing parameters should be able to go in and change it to halogen tail lights as it’s usually a selectable option in the computer, though you’ll likely have to pay them for their time. You could try and find something like VAG-COM/VCDS (for VW vehicles) or AlfaOBD (FCA) but for GM vehicles and change it yourself as well, but you’d need an OBDII connector and the appropriate software.
 
What you discovered about the cost of factory LED lights is going to bite 2nd and 3rd owners as all these LED equipped vehicles age. Maybe the aftermarket will step up. Curious if they both went bad in a 2019 or there was some unintended bodywork involved?

car was rear ended. Replaced the trunk and also the wiring harness to convert it to halogen. It was plug and play. It’s all genuine stuff. I actually ordered aftermarket LED options but the connectors on the lights didn’t match the harness. Then I went to the wholesale department at the local Chevy dealer and the cost was $1500 for all of them. The halogen set with harness was $300 used.

in the long run I think if the light was to ever go bad the later owners wouldn’t have to replace the whole housing but just the bulbs. The current Malibu base L trim still has halogen tails. It’s the LT and LTZ cars that come with LED
 
I’d try that, at least on one side. Autozone has same name brand LEDs, either Philips or Sylvania, and while they do cost a little, they’ve been reliable, which is more than I can say for anything I’ve tried from Amazon.
 
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