Hyper flash with new incandescent signal bulbs when driving and outside temp is above 85 degrees

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Aidry

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Bergen County
Hi
So I’m having issues with my 2013 wrangler sport left and right turn signals. They are incandescent bulbs not led and when it’s above around 85 degrees outside it starts to hyper flash on the left and right side.
Again they incandescent bulbs not led.
I change the signal switch and both signal harnesses in the back. Definitely something to do with heat and a resistance drop. Just can’t figure it out. Has anyone had this problem with incandescent bulbs. Again they are new bulbs. I have replaced them in the rear 3x’s. Front ones are fine.
 
Aidry said:
Hi
So I’m having issues with my 2013 wrangler sport left and right turn signals. They are incandescent bulbs not led and when it’s above around 85 degrees outside it starts to hyper flash on the left and right side.
Again they incandescent bulbs not led.
I change the signal switch and both signal harnesses in the back. Definitely something to do with heat and a resistance drop. Just can’t figure it out. Has anyone had this problem with incandescent bulbs. Again they are new bulbs. I have replaced them in the rear 3x’s. Front ones are fine.
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Given that you’ve already replaced the signal switch and the harnesses, it sounds like you're on the right track. Here are a few things to consider:
  • Ground Connections: Ensure that the ground connections for the rear signal lights are clean and secure. Poor grounding can lead to erratic behavior, and heat can exacerbate this issue.
  • Bulb Type and Compatibility: Even though you mentioned they’re new incandescent bulbs, double-check that they are the correct wattage and type for your Wrangler. Sometimes, even a slight difference can cause issues.
  • Connector Condition: Inspect the connectors for any signs of corrosion or damage. Heat can cause these connections to expand or oxidize, leading to increased resistance.
  • Heat Sensitivity: Since you mentioned the problem correlates with high temperatures, consider whether any nearby components might be causing excessive heat that could affect the signal circuit.
  • Flasher Relay: Although you mentioned the signal switch, the flasher relay could also be a culprit. If it’s heat-sensitive or malfunctioning, it may cause hyper flashing. Replacing it might be worth a try.
  • Harness Routing: Ensure the wiring harness isn’t routed near any heat sources that could impact performance, as heat can affect the resistance within the wires.
Hopefully, one of these suggestions helps narrow down the issue. Good luck, and keep us updated on what you find!
 
There is a fuse that powers the multifunction switch. I think it's M13 but don't quote me. Might be worth checking?
 
It think it has something to do with heat I just cannot find any wires that are laying on the exhaust or anywhere else where that gives off a lot of heat.
It does it as soon as it heats up and it’s above 80 to 85 degrees.
It didn’t do it all winter long or last year I replaced the 3157 bulbs with the same exact ones that were in there.
I have had this jeep for 3 years it came from Florida so there is absolutely no rust anywhere on the frame, so every ground connection is clean.
 
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