How are Signal Flasher issues diagnosed?
Signal flashers which are integrated into computerized components or circuit boards are still simple to diagnose, however they require a higher repair bill most times due to the need to replace the entire assembly they are combined with. On the other hand, signal flashers that are simply plugged into the power distribution center or junction box can be tested with any 12v battery and replaced just as easily. Testing an integrated circuit requires identification of the power wire and load (output) wire for the signal flasher where it enters and exits an assembly or control module. If the proper amount of power is fed into the relay, but the relay is either not causing power fluctuation or not sending power to the turn signals, it is faulty. This will call for the assembly to be replaced. However, a turn signal flasher that is plugged in can be removed, connected to a 12v power source, and tested with a test light. If the test light blinks, the turn signal flasher relay is good, any other result, it must be replaced.
How are Signal Flashers replaced?
As stated, there are a few types of integrated components that may require replacement due to the turn signal flasher being combined within that component. For instance, the multi-function switch or body control module may require replacement if the turn signal relay is integrated into those components. However, the classic style, or even the modern flashers that plug into the power distribution block can be pulled and replaced by hand most times.
RepairPal Recommendations for Signal Flasher issues
Purchasing a turn signal relay should be done with the understanding of how much load is to be placed on the turn signal relay. Even when purchasing a turn signal relay for a classic vehicle which uses a mechanical flasher relay. That is because if the load from the turn signal lights is not high enough, the circuit will not fluctuate. We recommend pairing the specifications for the old unit to the new unit, and avoiding purchasing aftermarket light bulbs for the turn signal if the load is not similar to the existing bulbs.