I was checking my owners manual to see if the coolant temperature warning light should come on momentarily when turning the key to the on position to perform a lamp check. It seems there is no lamp check function. I just figured that something so important should be tested to ensure it will work if it was needed. The only explanation I can think of is that this indicating light is redundant due to the digital temperature display that will flash when a high temperature is reached. So the question comes to mind, why bother putting a high temperature light on the dash in the first place? By the way.... this is about a '05 model