So, I've got the Celis Taillights installed. Without mounting the harnesses in the truck yet, I decided to hook them up and give them a test run. I plugged them in exactly as the hella instructions specified, and other than the parking lights, nothing functions correctly. When I turn the turn signals on, the brake light blinks, and the LED (parking light) flickers. When I turn the reverse lights on, the turn signal bulbs come on, as do the brake lights.

There's no way to possibly reverse the plugs. What's going on?

Thanks in advance,

-Evan

:rofl...The same thing happened to me at first...I was all like "WTF?!", then I switched the harnesses around, and all was good. The 2 harnesses are different...one for left, one for right.

:rofl...The same thing happened to me at first...I was all like "WTF?!", then I switched the harnesses around, and all was good. The 2 harnesses are different...one for left, one for right.
Hah. That worked. Actually, I emailed the Eurosport Design guy, and even on a Sunday, he replied within 10 minutes:

Evan,

Try 2 things. First, make sure you have the left harness plugged into the left taillight, and the same for the right side. Second, the ballasts are interchangeable, switch the ballasts and test them again.

If you can't figure it out install your old taillights and we'll ship you a brand new set first thing Monday. It's very rare for these taillights to be defective but it can happen. If they are defective we'll send you a new set Fedex express with a return label for the original pair.

Sorry your having problems. Let us know how it goes.