When I engage the multifunction switch to start the left or right turn signal, both the interior console left or right signal flashes fast, as do the exterior turn signals.

To the best of my knowledge, there are only two signals on each switch (front and rear). I don't see a side or top signal, but it doesn't mean I'm missing it.

I checked fuse #1 in the fuse box and it looks OK. I don't think the turn signal would have worked at all if the fuse 1 was blown.

I've got a cab/chassis setup with a utility box.

Any ideas on things to check.

Thank you.

 

Do u have LED tailights? If so, that is your problem

 

Bulbs burned out?

Are the lights LED's?

Lower amp draw will make the relay cycle faster, you can add load resistors to led's or a different relay.

 

got to get 10 characters

 

Not sure if the rears are LEDs. They are self contained units that don't seem like they can be opened up. I'll write down the part number and do a google search and then post the results.

Thank you.

 

OK - The red signal lamps don't have a part number on them. However, the clear/white back up lamps indicate they are Truck-lite part number 40204 which does not appear to be an LED product - Truck-Lite - Catalog Product : 40 Series Back-Up 4'' Sealed

Any other ideas?

 

Replace the relay.

 

What Joe said. Back in the day "heavy duty" replacement flasher relays would blink faster than a stock replacement. Perhaps due to the amp draw as AL mentioned.

 

One other thing you can do is to check your connection at the back of the truck where you plug your trailer in at. Open the cover for the plug and make sure it is not full of water and or corrosion. Simple check that cost absolutely nothing. Also look at how that plug is tied into the electrical system. It is a modular plug that goes between two stock plug fittings. Are those plug fittings or solder/wire nut connections dry and not full of water. After you have done the free stuff then you can pay for another flasher and see what that brings you.
Dwayne

 

x2

Had this problem on my '91. Changed relay....all good.