Hey guys, quick question on my OM 603 glow plug relay. The temp has been dropping a bit lately, and the wife noticed the car has been starting rough. I checked it this morning, and after sitting all night with an outside temp of about 30 degrees the relay only stayed on for about 10 seconds before it clicked off. That seems way too quick, as last winter I remember I could let it cycle for something like 30 seconds on cold mornings before it would click off. I feel like there is a temp sensor that controls how long it cycles for. Which one is it (there are like 3 on this car)? Also, what would be the best way to test it? Just to clarify, I am not talking about the glow plug light, but how long the plugs actually stay energized. Thanks for any help!

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