Coolant Leakage from Heater Core, Possible Leakage onto Passenger Side Foot Well on Mercury Milan

Problem Description and Possible Solution

Electrolysis can cause repeated failures of the heater core and radiator. The diagnosing technician should check for voltage present in the coolant, with the battery disconnected, because electrical current in the coolant causes electrolysis. Corroded or deteriorated parts should be replaced, and the coolant should be flushed. Ground straps can be added to help prevent future corrosion of components.

Problem Data
RepairPal Verified
Average mileage: 84,941 (55,000–105,000)
3 model years affected: 2006, 2007, 2009
7 people reported this problem
Viewing 1 - 4 of 4 problem details
Drain line clear, but water leaks under carpet on passenger side of car.
The front passanger side floor is wet on my Mercury Milan.I was told by a couple of friends it was the heater core. How much does the work cost for this job??
When in the car! I smell coolant in the cab of the car. What could be the cause of this and how do I find out where it's coming from
The electrolysis problem would not occcur if the heater core were thermoplastic. RIDICULOUSLY SIMPLE TO PREVENT.
I had the same problem with a 96 and a 97 Grand Am. I smelled the antifreeze and had to add coolant to them. GM had metal hose ends to a thermoplastic body. The hose ends corroded.

I can't believe that the instrument panel/dash board of this Milan must come out to replace the heater core. RIDICULOUS!