Down here in GA during the recent blast of winter chill I plugged my block heater in overnight to help cold startups. After work when the truck would cold soak all day in below freezing temps the 5.9 diesel took a long cranking time to start banging and popping with enough white smoke to kill all the mosquitos in the area if it was summer time. Anyway it was time to check my '00 2500 CTD for ailments causing this problem. I went online and found alot of info about possible causes. My wait to start light was working properly, but I wasn't getting the volt drop during the wait to start illumination. I didn't hear the intake heater relays click when troubleshoot ing, got 12v at the relay but none out. So off to Amazon for a $53 replacement relay, installed the new relays and turned the key to start the wait to start sequence. Still no volt drop on my volt gauge stayed around the 12 volt line. Hmmm, more online troubleshooting needed, OHMed out my grid heater to see if it was bad- it tested good with the easy end of the ground strap unbolted but when I checked the short gound strap at the grid heater connection I found it burnt and split.
So it was time to replace that ground wire, I used a 12" 4 guage battery terminal cable($5.99) and a replacement copper 4 guage cable terminal end with a 1/4" hole($3). I cut the 12" cable to match the size of the original and installed the new cable end onto the now 5" long cable. Bolted into place, initiated a wait to start sequence and yippee the volt gauge showed around 10volts and when I started the engine it cycled normally indicating the grid heater was now working normally.
So check that ground wire on your grid heater if your having problems. Pics show left over wire and extra terminal end

 

The pre 2003 model years used a non-conductive gasket for the grid heaters, that's why a ground wire was necessary. If you replace the gasket with new conductive gasket #2 then no ground wire necessary. JFYI

 

Good info. Always wondered why the extra ground wire. Thanks

 

Good info! How much is the newer gasket? Anyhow more time and money getting one, but would be a good modification in the future

 

Although you only need one gasket for a ground path for the heater grid to work there are two gaskets' top and bottom that are required.