I recently plugged in my block heater for the first time, and nothing happened. I bought the truck used and with this frigid weather as of late wanted to use it as truck cranked over very slow and barely started in sub zero weather. I've done nothing yet for diagnostics but hoped someone familiar could step me through a checklist. Is there a dedicated fuse/ breaker for this and is it under the hood in fuse box? If fuse/ breaker is good can the heater element be tested? Possibly a defective cord? Also is there any indication light in instrument panel when this is plugged in and operating correctly? Any suggestions are greatly appreciated. Thank you!

 

Nope, the block heater is it's own entity. After an hour or so, you should be able to feel the side of the block warming up, I can hear mine start to bubble as soon as I plug it in.

I don't hear of many block heaters going bad... more than likely the cord. Do you have a voltmeter/multimeter? Pull the cord off and check for voltage. If the cord is good, then check resistance across the block heater itself... if it reads open, the element is bad.

How long did you plug it in for?

Here is the block heater location...
https://www.dieseltruckresource.com/...nstall-223768/

 

Check the cord. Mine had a bad wire next to the plug.

 

Thanks guys. I'll check as you described. I had it plugged in overnight. The link to the block heater cord install was awesome. I'll post my findings once I get the time to complete. Thanks again!

 

I would expect about 6 ohms or so across the plug. If it's open (infinite) then either the heating element or the cord is bad.

Might also check that there is power at the outlet and extension cord you are using. If it is equipped with ground fault interrupt moisture at the plug could have tripped it.