Hey Mercedes Diesel fans: I need help! The glow plug light in my 2005 E320CDI comes on and then goes out very quickly but the "Check Engine" light stays on after the car is running. Had the fault code read at Auto Zone and they showed me that the alleged fault is the "Glow Plug Relay". Have looked it up and know what it is supposed to look like. However: I can NOT find anything that looks like the picture anywhere in the engine compartment. Can anyone tell me where the relay is located for sure? I can clear the check engine light and it will stay off for one or two days but then comes back on so apparently I DO need to replace the relay. HELP!