Greedy wrote:I asked the same question years ago but didn't get an answer. Figured it ain't broke so forgot about it.
My 2006ML has 2 plugs both close to each other in that position, one from the engine temp sensor, one from the aircon on sensor, so it will switch the thermo fan on as required (for tropics/ Thailand etc). The rest of the world does not know that we have some high summer temps and plenty of tropics here as well. I put a 10 inch after market thermo fan in the provided position and wired it to the dash with its own switch, all for $50. I can give the aircon some help starting and if in traffic or if I tow or climb at low revs under load, turn it on to check the engine temps against my scan gauge digital read out..I would seek more advice from experts regarding the current overheating solution provided by Mitsu on the MN's. For these reasons, increasing the cooling system pressure by close to 20% adds stress to the entire cooling system, reducing conductivity of the coolant by adding 20% more glycol reduces efficiency of coolant in terms of heat transfer, this does allow temperature increase without boiling occurring and therefore coolant failure but adds further stress to the system by allowing a higher normal operating temperature thru' the entire engine system. What a good idea the original designers had in mind to have a back up cooling thermo fan in the system and providing for that with all the mounts, plugs in place just the relays left out of the fuse box in the engine bay, I just rejigged that design idea that as I did not want to pay the $400 OEM version, it would have cost Mitsu another $400 to provide this to everyone in the first place or as an option, would you have ticked that box on the new item if it was offered....I also appreciate that there are the casting and quality control issues with the MN engine block contributing to heat induced engine failures outside of the scope of my comments above...
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