SOS....Engine heater failure?

Helga is my 2007 Duramax gal. I was finally able to locate the heating block plug thanks to YouTube and not the many GMC dealers or garage workers I've pestered over the years, but it doesn't seem to work. Is thete something else I need to do so it will work? Does it need a fuse? We have a diesel Ford and Dodge that work fine but I cannot figure out how to keep Helga warm on those cold nights. The end of the plug appears normal soo I assume it does not have a thermostat although I've been trying to use it in near zero weather.
Any help is greatly appreciated!
Rhonda
~R~

Hi Rhonda
Welcome and Happy New Year
It should just plug into an extension cord to work.
If you are really quite when you plug it in you should hear it start to heat the water like an electric kettle.
Or if you have a volt meter you can check to see if the heater is good by using the continuity setting and put a probe on each flat prong on the heater cord if the heater is good the tester should make the same sound as when you touch the prongs together.
Thomas

Welcome to the board!

These engine block heaters are one of the more reliable components on these trucks. I've had a couple block heaters through the years that would trip a GFI (Ground Fault Interrupter) 3-prong outlet, but the heater would work normally when using a non-GFI outlet. I've yet to notice any problem otherwise.

Jim

Follow the cord to it's other (heater) end. It's possible it is unplugged on that end.