After replacing tail lights with LED, passenger side running lights are not working

2003 JEEP WRANGLER
110,000 MILES • 4.0L • 6 CYL • 4WD • MANUAL
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HDFATBOY2005
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I bought new replacement rear LED tail lights. Hook both up and no running lights on passenger side. Driver side all works. Everything else works, turn signal, brake light just no running light on passenger side. I checked the running light wire and driver side was 11.4 volts and passenger side was 4.6 volts. Would that cause the light not to light up or is it just the LED lamp bad?
Thank you.
Feb 4, 2018 at 7:14 AM
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PATENTED_REPAIR_PRO
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Sometimes LED bulbs have polarity. try removing that left rear taillight bulbs and then test that voltage again at the right rear.
I do see the right rear taillight wire also splices to and feeds both front running/parking lights, so do the front still work?
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Feb 4, 2018 at 8:08 AM
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HDFATBOY2005
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Yes the fronts still work.
Okay, I will try to switch them. The only thing the left has a licence plate light so i would have to switch them back. Could a dirty connection cause low voltage reading?
Thank you.
Feb 4, 2018 at 8:19 AM
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PATENTED_REPAIR_PRO
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A dirty connection could cause a loss of voltage.
If the fronts are working okay, I do not see no need to worry about the left rear then, simply because the splice for it is before the splice for the fronts. so, check the voltage again on that black/yellow wire where it meets up with the other black/yellow wires, the one that feeds the fronts and the one that comes from the multi-function/headlight switch.
Now where exactly this connection or splice is located, the repair manual does not say, so I suggest you just follow the black/yellow wire from the right rear light assembly to find it.
First of all, it appears there is a connection near the right rear light assembly, check the voltage there first before continuing on back toward the light switch.
Feb 4, 2018 at 8:29 AM
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HDFATBOY2005
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Okay, I will clean the right side connection. It looked rough. Then I will check the wires back.
Any chance it could be a bad LED light in the taillight? If it has around 4.5 volts would the LED light light up a little or is that not enough power to light up the LED light?
Thank you for the help.
Feb 4, 2018 at 8:42 AM
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PATENTED_REPAIR_PRO
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No, it would not be the bulb, because you have already tested the voltage and 4.5 volts probably is not enough to light the bulb bright enough to see, maybe if it was night time.
Feb 4, 2018 at 8:53 AM
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HDFATBOY2005
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Okay, I will check the wires back.
Thank you for the help.
You think cut wire or something else?
Feb 4, 2018 at 9:03 AM
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PATENTED_REPAIR_PRO
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Cut? Probably not, since that would usually mean no voltage at all, perhaps broken copper wire strands or maybe a rusted connection.
Feb 4, 2018 at 9:30 AM
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HDFATBOY2005
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Okay, I will check the wires back.
Thanks again for the help.
Thank you.
Feb 4, 2018 at 9:31 AM
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PATENTED_REPAIR_PRO
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You are welcome.
Feb 4, 2018 at 9:32 AM