Grid heater not working

[Black98cummins]

I searched this an didn't find anything usefull my grid heater is not working I know to check relays and where else should I check or what else would cause this not to work and if it is the relays where's the cheapest place to get em r they a dealer only item or what thanks

 

[12vriviera]

You just needed an isolated ground starter relay, there is a part number that autozone has, for a jeep cherokee I think, like 12 bucks, the ecm controls the relays so if you aren't getting control power to the relay then your ecm isn't happy