Thank you for all the time and information, as I'm dealing with these issues on my 2017 L5P cab and chassis truck now, it's quite frustrating, I'm glad to hear that you found your issue. Someone had broken the cell light out for the Check Engine light and the Glow plug Light prior owner. So I am going to assume we may share the same module as culprit. Going to send my Cluster to be fixed and CK the Glow plug module next. Hope your still going strong since your fix last input. Ty Daryl