Sometimes it pays to have family-level access to a mechanic. I took a trip with my wife and two kids recently (middle of March) to the San Antonio, Texas area (Boerne, specifically) to visit my in-laws down there. We thought we were going to escape the Utah winter for a week, but our luck apparently wouldn’t allow it. Along with the much-needed rain that fell in Texas while we were there, the temperatures dropped to the low 40’s. Those kinds of temperatures in Texas feel like below freezing temperatures in Utah.
During our short trips around the San Antonio area, I noticed that the temperature in the Ford Expedition we were driving seemed to be the same chilling temperature as the outside air. At first I thought my wife’s family was just so averse to Texas’ summer heat that they preferred to stay as cold as they could as long as they could. The short trips around San Antonio were bearable anyway, so I didn’t complain.
Then we took a trip to Houston. After a short while, I noticed that everyone in the car was trying to find ways to get warm. My mother-in-law apologized that the heater hadn’t been working for the previous month or so. When she asked for some gloves to keep her hands warm on the cold steering wheel, I figured it was time to go into troubleshooting mode. I messed with the dials on the console for awhile with no success. Then I opened the owners manual and read for awhile, finding no tips for what to do if your Ford Expedition’s heat fails to work. I finally removed the temperature control dial to see if something was preventing the air from switching to hot from cold. Still nothing obvious stood out. Instead of dismantling the car from the inside out, I decided to call my dad, who is a mechanic.
He told me that the first thing to check when an automobile’s heater isn’t working is the coolant level. For some reason beyond my automotive expertise, if there isn’t enough coolant (water, antifreeze, or a combination of the two) in a car’s cooling system, the heat won’t work. My mother-in-law’s Expedition helped us find that out the hard way. I asked her if she’d had her oil changed recently, and she showed me the sticker that indicated she had. I then asked if, during the oil change, the quick lube worker had checked the fluid levels on her car. She didn’t know for sure what was done to her car during the oil change, so we decided to have a look at our next stop. By that time, we were tired of switching the defrost off each time we were too cold to stand it any longer, then switching it back on when the windshield became too fogged up to see outside the car.
After eating lunch at a Whataburger in some town that’s about the halfway point between San Antonio and Houston, I refilled my soda cup with water, and I poured it into the coolant reservoir on the driver’s side of the car. I tried to access the radiator cap, but apparently the designer’s of the Ford Expedition don’t want people accessing the radiator cap without at least a few handy tools, which is a few more than what I had. After emptying a quart or so of water into the coolant reservoir, I went back into the restaurant to get more. My father-in-law (who had been following behind us in another car), recognizing me as the “Wannabe Mechanic” practicing my automotive skills on a substantial investment of his, asked me what I was doing. I explained what the Online Mechanic had suggested, and he asked me to make sure I was putting in a mixture of half antifreeze / half water, as recommended for most cars.
Since Whataburger doesn’t have a mixture of half antifreeze / half water at its soda refill station, I had to cross the street to a service station and pick some up there. I brought the coolant back to the Whataburger parking lot, emptied it into the coolant reservoir, and watched it drain down into wherever it drains. (I’m guessing it goes into the radiator.) I then cranked up the car and turned on the heat. Voila! We had heat.
If you run into the same problem, I’d suggest you try what I did, except much earlier. Apparently there are lots of people who bring their automobiles into repair shops after having endured significant periods of freezing only to learn that their coolant was low. The simple addition of antifreeze and water could fix the problem.