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I went ahead and ordered the rear lights and resistors as listed by PDX (thank you for taking time to post those). Have you attempted the install yet? I think you are further along in the process than me how everything turned out
I finished the install this weekend and it went mostly smooth. I purchased trim removal tools from Harbor Freight to use to peel up the plastic trim in the back to access the light housing, which mostly worked well but i partially damaged 1 clip (no big deal, it still works and can be replaced later if need be.

Hard part for me was finding a place to put the resistor. There is an opening below the light between the frame and the bumper, with a slight flat spot. I just used double sided 3m tape and installed the resistor on this small flat spot (make sure to clean it off good first so the tape can grab it). Since the resistor will only be on when turn signals are activated, and turn signals are rarely on and when on not for a long period of time, the double sided tape should work fine.

Google how to install the resistors so you can see a quick tutorial. Same with how to replace the brake lights as that will show you how to remove the trim. Basically for resistors look closely at the turn signal socket (verify it's the turn signal before clamping the resistor onto it) there are 2 wires, you slide one wire into the end of the supplied "T" connectors that's open at both ends, insert 1 wire from 1 resistor into the end of the "T" connector that is only open at one end (plastic cap at the other end) and crimp it on. Repeat for the other wire with the other wire from the resistor. Then repeat on the other side. Just make sure you mark the brake and turn signal lights before you start removing bulbs/crimping to make sure you get the right one. To make it easier to work I unscrewed the brake and turn signal sockets from the housing and disconnected the LED tail light clip so i could just remove the light housing until i was done with the resistor install and was ready to reinstall the lights and the housing.

You may need to rotate the bulb to make sure it goes in fully and securely into the socket, and test it out obviously before putting everything back together. Just make sure to read the product page for the bulbs to get the right resistors, the Endpage ones recommended by PDX say to use the 50 watt resistors (there are 2 versions, 25w and 50w, make sure to get the 50w)
 

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Thanks for all the details, much appreciated! I watched some YouTube videos on wiring resistors and my concern was, once opening the housing, where the resistors would fit. And yep, I bought the wrong resistors too... bought the 25w. I didn’t think I would need more since they would only be powering the rear turn signals. The front would be different ones, but not needed since I already have LED in the front.
 

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Thanks for all the details, much appreciated! I watched some YouTube videos on wiring resistors and my concern was, once opening the housing, where the resistors would fit. And yep, I bought the wrong resistors too... bought the 25w. I didn’t think I would need more since they would only be powering the rear turn signals. The front would be different ones, but not needed since I already have LED in the front.
Considering how infrequent current would be drawn through the resistor i'm not sure if there's a problem using the 25w or if you need to return/exchange them for the 50w version. Safest bet is to go with what the light manufacturer recommends, which is 50w. I almost made the same mistake until I noticed there were 2 resistor options, and looked back at the light and it said 50w.
 

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Actually, you don't need the 50W resistors - 25W should be enough, and being physically smaller should be easier to mount. The purpose of the resistors is to compensate for the drop in current for the LEDs, and return the current to similar levels as the OEM bulbs. The rear turn signals use 21W bulbs; the LED uses something like 4W (there are conflicting specs on Amazon's page). That means that the resistor only needs to draw 17W. A 10Ω resistor at 13.5V draws 18W, so close. The front turn signal filament is rated for 28W, the LED for about 5W, thus 23W is needed. An 8Ω resistor draws [email protected], so that is the right size. Note that neither of these is dissipating more than 25W, and as has already been pointed out the load is intermittent, at about a 50% duty cycle, so actually a 15W resistor should be enough. The 25W will certainly be adequate.
 

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Actually, you don't need the 50W resistors - 25W should be enough, and being physically smaller should be easier to mount. The purpose of the resistors is to compensate for the drop in current for the LEDs, and return the current to similar levels as the OEM bulbs. The rear turn signals use 21W bulbs; the LED uses something like 4W (there are conflicting specs on Amazon's page). That means that the resistor only needs to draw 17W. A 10Ω resistor at 13.5V draws 18W, so close. The front turn signal filament is rated for 28W, the LED for about 5W, thus 23W is needed. An 8Ω resistor draws [email protected], so that is the right size. Note that neither of these is dissipating more than 25W, and as has already been pointed out the load is intermittent, at about a 50% duty cycle, so actually a 15W resistor should be enough. The 25W will certainly be adequate.
Good to know, thank you. So glad to chat with such knowledgeable folks on here.
 

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The recommendation most commonly seen is for 6Ω/50W. A 6Ω resistor at 13.5V is consuming 30W, so the 25W would not be enough in that case. But since the OEM lights never reach 30W, further reduced by the LED consumption, a 6Ω resistor makes no sense at all. The result is a total load on the circuit of 35W (for the front flashers) instead of the OEM 28W. It may be that the extra 7W will do no harm, but more importantly it is doing no good either and has the potential for damage due to overloading. The idea seems to be that throwing such a large load at the problem will guarantee there is enough current - about as sloppy a bit of thinking as one might expect.
 

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The recommendation most commonly seen is for 6Ω/50W. A 6Ω resistor at 13.5V is consuming 30W, so the 25W would not be enough in that case. But since the OEM lights never reach 30W, further reduced by the LED consumption, a 6Ω resistor makes no sense at all. The result is a total load on the circuit of 35W (for the front flashers) instead of the OEM 28W. It may be that the extra 7W will do no harm, but more importantly it is doing no good either and has the potential for damage due to overloading. The idea seems to be that throwing such a large load at the problem will guarantee there is enough current - about as sloppy a bit of thinking as one might expect.
So, the bulbs I purchased as recommended in your chart, produce 5.5W each. Paired with the 12V 10Ω, 25W resistor it seems like I should be good then?
 

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The recommendation most commonly seen is for 6Ω/50W. A 6Ω resistor at 13.5V is consuming 30W, so the 25W would not be enough in that case. But since the OEM lights never reach 30W, further reduced by the LED consumption, a 6Ω resistor makes no sense at all. The result is a total load on the circuit of 35W (for the front flashers) instead of the OEM 28W. It may be that the extra 7W will do no harm, but more importantly it is doing no good either and has the potential for damage due to overloading. The idea seems to be that throwing such a large load at the problem will guarantee there is enough current - about as sloppy a bit of thinking as one might expect.
I only replaced the rear signals as the fronts in my 19 are already oem led.

As I already bought and installed 50w resistors for the rear turn signals (1 each side obviously) as per that's what the light manufacturer recommends, is that going to be ok? Or are you saying it will do damage and should be replaced with 25w resistors instead?

Being as I already have the 50w installed and working obviously I'd prefer not to have to redo it all over again

Sent from my SM-G975U using Tapatalk
 

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As I already bought and installed 50w resistors for the rear turn signals (1 each side obviously) as per that's what the light manufacturer recommends, is that going to be ok? Or are you saying it will do damage and should be replaced with 25w resistors instead?
Watts (W) is a measure of energy, in this case heat. The 50W rating means that the assembly is capable of dissipating that much heat (50W) and not overheat. So your resistors have twice the capability at 50W as the 25W ones - a good thing.
 

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Yep. I bought two sets for the rear brake lights and rear turn signals.
2 sets of lights (4 bulbs, 2 rear brake and 2 rear turn signals). You only need 1 set of resistors (2 total) for the rear turn signals, rear brakes don't need them. And if you have 17+ then your fronts are already LED's and you don't need to do those either.
 

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2 sets of lights (4 bulbs, 2 rear brake and 2 rear turn signals). You only need 1 set of resistors (2 total) for the rear turn signals, rear brakes don't need them. And if you have 17+ then your fronts are already LED's and you don't need to do those either.
Exactly what I bought. Did you happen to take any pics of your install?? I know you explained where you mounted the resistors but hard to visualize. I’m sure I will understand once I pull the taillight off.
 

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Exactly what I bought. Did you happen to take any pics of your install?? I know you explained where you mounted the resistors but hard to visualize. I’m sure I will understand once I pull the taillight off.
I didn't unfortunately. When you take the tail light off, below the outer edge of the tail light housing you'll see an opening between the frame and the rear bumper. There will be a small flat surface on the frame in this opening (most of it is curved). It's small but should be very visible once you take the light off and are looking for it. It's the only place I found that had a flat surface that was also in close proximity to the lights as the wire leads on the resistor aren't super long and thus can't reach super far.
 

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I didn't unfortunately. When you take the tail light off, below the outer edge of the tail light housing you'll see an opening between the frame and the rear bumper. There will be a small flat surface on the frame in this opening (most of it is curved). It's small but should be very visible once you take the light off and are looking for it. It's the only place I found that had a flat surface that was also in close proximity to the lights as the wire leads on the resistor aren't super long and thus can't reach super far.
Gotcha. Thanks
 

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Drove tonight for the first time at night since swapping the rear lights for LED's and it makes a HUGE difference. Looking in my rearview I can see both brake lights and turn signals reflecting light off of street signs over 100 feet away, when before even right next to them I didn't see light reflecting with the incandescent brake lights and turn signals. Reverse lights also appear to be a noticeable improvement, however I haven't really been in a spot that's pitch black to test the added visibility when in reverse.

On a side note, I also got the LED's to swap the rear hatch cargo lights and under door courtesy lights to LED and that makes a nice difference as well. I also got lights to do the glove box and center console (under arm rest) but when I look in the center console it would appear there are only 2 small lights on either side, both of which already appear to be dim LED's. The glove box however does have incandescent. So not sure if I missed it or if they changed it (I have a 19 MDX) but I didn't see any incandescent lights in the center console to swap to LED.

Thanks again to PDXsailor for all the helpful info, made it a painless and easy process!
 

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Done and done! Replaced the brake lights and rear turn signals with resistors. Everything looks and works great! So I may have broke a clip or two when removing the black plastic trim piece but nothing a little super glue couldn’t fix.
Attached the resistor to the only free space of metal using double sided tape. Not gonna lie.. I was nervous about tapping into the wiring but as of now, it appears all connections are solid. Thanks to Bobby and PDX for your instructions!
 
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