Want to change to LEDs and don't want to add resistors?

There seem to be two types of flasher relays 2G Tacomas can have:

Most common (there's an electronic flasher replacement available):


Least common (there's squat available for it; same relay as Tundra):


If you have this second type of relay, here's how you mod it to balance the load of resistors on one set of LED turn signal bulbs (NOTE: One set only. Tried it with LEDs front and rear and it DID NOT WORK.)
http://www.tundratalk.net/forums/tu...sher-relay-modification-led-turn-signals.html

Confirmed this works on my '15 Tacoma as well as it has the very same relay.

 

Am interested in why you don't want to add load resistors...If the load resistors are connected to the rear turn signal bulb circuit (stub harness for the light assembly) you get the same result as modding the resistors in the flasher module itself to correct hyperflash. Either way you're maintaining the same (appx) load on the flasher circuit & so the resistors are engaged only during turn signal operation. Appx 4 ohm resistor behind each tail light should provide enough load for front/rear leds.
Just trying to understand.

 

Many reasons:
- hot resistors
- more electrical parts being added
- splicing required
- adding more weak links
- ever been behind the tail lights? there's squat for space.

 

Andrew, is this a possible item that TRS would be willing to make and sell? Well produce on that can run both LEDs on Front & Rear turns.

Knowing Toyota, I am sure that the Tacoma/Tundra isn't the only one to use this type of DRL/Turn Signal Relay.

Base it off your bulbs and you could sell it as a Toyota package or have a discount code when you buy all 3 (front, rear and relay).

 

Unfortunately not something we want to get into. It's best left to the few of us who do the work ourselves.

 

First, there is plenty of room behind the tail lights for resistors. I added front amber DRL/turn signal and amber rear turn LED's. LEDs were "a gift" from a lighting company rep so no spec's were available. Considered modifying a 12 pin flasher I picked up from a salvage yard, but after some thought, decided to use resistors instead. Used silicone sealant to seal the wire taps, although there is no evidence of moisture behind the lamp assembly. Used a resistor per lamp, stainless sheet metal screws to attach the resistors to the sheet metal behind the lamp. After a couple of minutes of flashing, the resistors get moderately warm and the heat is dissipated well through the sheet metal. I would not worry about any of the issues cited as reasons not to use resistors.

 

I'd prefer an oem style solution w/0 resistors too... if I could find one. Agree that there's splicing and heat involved, but the splicing is on the stub harness on the tail light assembly, not on the main harness so mod is minimal. Heat is only when turn signal/flasher is in use which is fairly intermittent. Yeah, they're a weak link; actually my solution was to add another socket/bulb behind each tail light to add resistance (only added LEDs in front). They're cheaper than resistors, last indefinitely and already had parts in my junk bin. So there is plenty of room.
Just my .02.

 

Actually, the "weak" link in automotive lighting are bulb filaments. My interest in LED's is the solid state nature and service life 100,000 hrs plus, as well as the aesthetic qualities. Adding a bulb for the needed resistance is certainly a viable option, but, they don't last indefinitely. You can source resistors for a couple of bucks apiece, almost the same price as an 1156 incandescent bulb. I would also prefer an OE solution, but I discovered that even modifying the spare 12 pin flasher I had was "hit or miss" because of variables in LED bulb power requirements, outputs etc. I considered adding variable potentiometers to the flasher to "dial" in the resistance, but installing fixed value resistors was a much easier and proven fix.

 

I'm a career firefighter for 10 years. I've personally had 2 car fires attributed to load resisters. User error? possibly...but if you change out an 18 dollar part, you're done. Simple. Easy. Safe. Do it.

 

I'm not sure which 18 dollar part you are referring to, there is no "change out" flasher for late model Tacoma's. 12 pin flashers need to modified to avoid LED hyper-flash. I have a spare 12 pin flasher, but was not comfortable with the mod or figuring out how much of a resistor was needed to be added to accommodate LED's where the specs were unknown. I agree that a fire is a possibility when any non O.E. electrical component is added incorrectly. I suspect that a resistor fire occurred when the resistor(s) was not secured to a metal frame part to act as a heat sink, for example zip tieing the resistor to a wire harness or leaving it hanging loose. The resistors I used in my installation were ceramic, wire wound, and metal encased. Until someone markets a 12 pin LED flasher, properly installed resistors seem to be the only viable option if you want to install LED's in your late model Tacoma.

 

Let me play a bit of devil's advocate. I don't see the appeal of LED replacement bulbs. I, for one, do not think they look better. Yes, the bulbs last longer, but I don't think they are worth the cost trade-off. In my 07 Taco, I've replaced three bulbs; two remain OEMs. That's about $7.50 of bulbs. How much for the LEDs and resistor's? Yes, they consume less energy, but in overall energy usage, that usage is a drop in the bucket.

That being said, I do believe in LED replacement bulbs for brake lights; I have blinking LEDs brake lights on my Taco. Safety is the motivating factor here; LEDs light up quicker than incandescent bulbs. That split second can make a difference.

 

By the end of the decade, every light on every vehicle sold will be an LED - Source: Carnac

 

Weak link? I disagree. I've had autos for 10 years without ANY burnout of turn signal bulbs. I lose a few 194's and especially 168 bulbs which are hotter (used in license plate illumination) but absolutely never a front or rear turn signal. They just don't run enough to get continuously hot enough to fail quickly. YMMV though. For me simply installing a socket behind the tail light and the hyperflash was solved; if this bulb does burn out it should be rare. The bulbs are rated for about 2000 hours, and with intermittent (turn signal usage) this is a lot of driving...where they'll burn out relatively quickly is in DTRL usage.

In the case of the front DTRL's the sockets were starting to discolor after a couple years with the Krypton bulbs running full time. The LEDs resolved that. I also use LEDS in the front side markers, and license plate illumination. ALso one superbright red LED in the high mount stop light (other 2 are stock bulbs) Beyond the heat problem, DTRL's LEDs help reduce the load on the alternator.. (assuming LED is 20 percent of incandescent load, 2.23 amps for stock krypton bulb * 2 * .8 = about 3.5 amps savings) . Not a lot but I'll take it.

 

In the FWIW category, attached are pics of my mod to DTRL LEDs (non-switchback) hyperflash fix.
The green stripe wire on the rear turn signal bulb was Y-Spliced to get the connection, a insulated crimp-on disconnect to the additional socket light, drilled a hole for ground (minimize wire mods on harness) using wire nut to connect ground wires. Socket is mounted in cutoff prescription bottle to protect the bulb. It actually fits well in a space behind the light. Used tape and three wire ties to be certain y-splice was tight.

 

Just a thought, although not reflective of your personal experience; the reason you can buy a single or dual filament 11xx series incandescent bulb for a buck, is that they manufacturer them by the millions, because they "FAIL" at the same rate.

 

That's the thing with the flashers, lots of 2nd gen Tacomas are wired to use the front blinkers as the DTRL, so the bulbs which were designed to be used for flashers and brake lights burn out relatively frequently.

 

I am enjoying reading all these threads, question.

Why not replace the outside resistor wire on the DRL/Towing Relay with a potentiometer. This way the resistance could be adjusted for both STD / LED bulbs.

The cover states T/S: 21 (23) Wx2+(0-8) W, 27Wx2, I believe this means it’s looking for 27 watts or more before you get that hyper flashing issue, below is the value of one STD light bulb.

 

Is that the 8-pin or 12-pin unit?

Those wattage levels aren't power thresholds before hyper-flash kicks in, since the hyper-flash is triggered by too much impedance (therefore too little power consumption) in the bulb circuit; that's why the corrective resistors wire in parallel to the bulbs (decreasing net impedance/increasing total current and power) rather than in series (increasing impedance/decreasing current and power). Too little impedance will eventually blow the fuse on the circuit, which may be sized to protect the flasher unit among other components. I learned from experience that the ohms needed to eliminate hyper-flash is different for the front vs rear on these trucks; 10 ohm resistors worked fine on the fronts (used them instead of the standard 4/6 ohm units to reduce heating of the resistors which are on full time by reducing current/power), but I needed to run two in parallel (making 5 ohms equivalent) when I got to swapping in the LEDs on the rear end.

There is a way to modify the flasher for LED bulbs by increasing the internal resistance in elements RS1 and RS2 (filing down the two metal hoops on lower/right corner of the PCB in your picture). This could also be accomplished by replacing these two elements with potentiometers, but nobody seems to know the specs on the range of resistance those pots would need to cover for this application, it's possible that there's no component available covering a low enough range and with the proper sensitivity to tune the particular circuit in this flasher unit (there are other units for other vehicles which have pots built in to adjust frequency, but those may well be based on a different basic circuit and might not translate correctly).

 

??? Yes,,, to little power consumption... "I believe this means it’s looking for 27 watts or more before you get that hyper flashing issue" meaning if one bulb was removed or something would cause too little power consumption.

So, why wouldn't a 150 Ohm potentiometer work.. If shaving down the resistor loops RS1 and RS2 changes their resistance then why wouldn't a potentiometer do the same thing.

 

A potentiometer would work as a replacement for the rs1 and rs2 components to make the unit adjustable, but 150 ohm is probably too high, even for what the final resistance on the properly filled down ones would be. Based on this write up, the "LED" appropriate resistance range is 65-250mOhm, and from the grinding mod write ups, baseline resistance would be about 1/4 of that, and the element needs to handle at least 10W power throughput. This means you'd need a pair of pots with a resistance range from .01-.25 Ohm with sufficient power handling and pin spacing similar to the width of the hoops on the flasher PCB; 10 Ohm power resistors are definitely easier to find and are almost certainly cheaper and easier to install compared to desoldering and replacing those components in the flasher unit.