Emergency Flashers Don't Flash - why?

There are two common causes of fast flicker instead of proper blink

1: A change of light bulbs.... USe of the SEPCIFIED lamps is necessary so long as you use the SPECIFIED flasher mnodule... There are many flasher modules, the Standard ones are designed to flash a specificed number of lamps. Now this is a good thing because on, say may car. If one of the turn signal lamps fails, It will rapid flash letting me know I"ve got a BOB on my hand (Burned OUt Bulb)

IF you switch from Standard lamps to LED's this can cuase rapid flash
ANd from 1141 to 1156 will also affect the flash rate.


HEAVY DUTY flashers however,,,, work differently they should work with one lamp, or 10, 1141 1156, or LED (Though they may need a few LED's to work).

Check all you lights.. and put in a Heavy Duty flasher,

Oh, how to tell if you have an HD or SD flasher.

SD flasher,. the instant you turn the switch the lights come on, then off, then on, then off

HD. The lights come on 1/2 flash cycle AFTER you turn on the switch so the pattern is off-on-off-on-off-on

This is because the HD flasher is "normally open" and as the element heats it closes the switch and shorts the heater.

My issue with my toad was caused by soysauceitis. At one time dependable flasher brands that just quit after several months. No LEDs, no shorts, no longs, nothing but failure in heavy traffic and BOTH times it was north of the border. You have not seen misery until you lay on your back on the floorboard, reach up to your elbow extract the old flasher then braille a replacement into the socket. I was pulled over in San Diego, and had to argue with the cop that old fashioned, out the window hand signals did not deserve a citation. I purchased a blowup proof Sure Power electronic flasher. The mechanic in Tijuana did not have rail-thin arms. He extracted his arm minus a strip of skin about 8 inches in length. Bleeding. He refused a tip. The MoPar flasher failed. Then A Warner. Then an Ideal. The last two were long heavy duty flashers. The Sure power will flash with 30 milliamps of load. It has an 80 amp 200 volt power transistor and is short and reverse polarity proof. One spec has it dumping into a short for forty plus hours. I wired a buzzer into the circuit then throttled the audio with duct tape.

And no one is bothering to keep records of failures. Wotta hoot. The 1157 light bulb used to last for many years. The 3157 lasts perhaps a year if night driving or stop & go is common. Yup, real progress.

As I said early on, it would help to know what RV the OP has. The Ford F53 chassis, for instance, uses a single flasher for both the directionals and emergency flashers.

Paul1944 wrote:
I just traded for this coach so I'm going through a tough learning process. One thing that I noticed is that my emergency flashers do not flash off and on, they just flicker very very fast, what could be causing this?

It is called "hyper flash" and typically caused by one or more bulbs being blown out OR incadescent bulbs were replaced with LED lights on NEWER vehicles..

LED lights have less current draw and look like a bulb is out to the flasher module.

For those stating to replace the flasher module, that is not always the case in newer vehicles. Many newer vehicles use the body control module (computer for the vehicle body functions) to detect the bulb current and decide to hyper flash.. the body control module is not something that is easily or cheaply replaceable and if you replaced would still do the same thing.

The fix for newer vehicles with body control module is to add a LOAD RESISTOR when using LEDs.

Older vehicles replacing the mechanical flasher module with a electronic (or HEAVY DUTY) module will typically fix hyper flash but on older vehicles hyper flash is caused by TOO MUCH CURRENT DRAW (IE shorted wiring or too many incadescent bulbs).

Older vehicles with mechanical flasher the flash rate slows or even stops flashing with a bulb out or LEDs..

Tell them you want the HD model

Take it with you to the Auto parts and they can Match it...

Had 1 of those go out on my truck,under the hood in the engine fuse block,usually a Square little box labeled emerg flasher.Mine was about 1 inch x 1 inch.Or could be called Turn signal.

Go to auto parts store

Ask for ELECTRONIC FLASHER

Need to replace flasher with HD model. It wont care about load.

Sounds like either the bulbs have been changed to leds or the flashers have been messed with.