There are a couple of possible solutions to the problem. One of the great benefits of LED bulbs is lower power consumption, but for vehicles that have thermal flasher relays installed, this will require some changes. When bulbs are changed from the factory installed incandescent bulbs to LED or SMD bulbs, the current draw (or load) to the flasher is reduced. As long as the total load is in line with the flasher relay’s requirements, the system will function without any issues. This is why some changes to LED bulbs, have no effect on the function of the system. In other vehicles, the minimum load requirement may be much lower than the load created by the vehicle’s bulbs. In some cases, the load maybe very close to the minimum required to make the flasher cycle. The auto manufacturer selects a flasher for the vehicle that best matches the “load” created by the bulbs in the turn signal system. In some vehicles that have a “bulb out” feature, the flasher will increase the blink rate and make the bulbs flash rapidly to notify the driver that there is a bulb out in the system. In some vehicles, when the load drops below the amount required by the flasher relay, the relay will not reach temp and the bulbs will not flash. The amount of current drawn by the bulbs is required to properly activate the thermal flasher.

The cycle of heating and cooling results in the lights going on and off at an interval, known as the blink rate. Once it is cooled, it turns on again until it reaches its shut off temp.

When it reaches a certain temperature, it shuts off until it cools down. This type of signal flasher relay work by heating up with the current for the bulbs passes through the relay. In many vehicles, the signal flasher is a thermal flasher design. The reason that the turn signals suddenly stop working after LED or SMD bulbs are installed has to do with the load put on the signal flasher relay. We recommend a couple different ways to address this problem, but first it is important to understand why there is a problem. Taillights/Marker Lights Not Flashing or Rapid (Hyper) Flashingįor some vehicles this is a common problem after updating the tail lights and/or other signal lights to LED/SMD bulbs.

Rodstar turn signal flasher led