Do you have single or dual zone climate control?
Posts by metalmike187
1 - 4 of 8 Posts
Let's start with the blower motor resistor. Good place to start as they can get corroded and cause all sorts of HVAC issues. I pasted a video below that should help you get started.
The first thing (which I assume you did already) is to inspect the resistor visually. Look for obvious signs of corrosion and burns from overheating. If you see signs of overheated connectors, replace the blower resistor and its connector. If you want to do a quick test of the blower resistor, you can check the resistance of each of the resistors with a multimeter as follows: set the tool to read ohms (a measurement of resistance) and connect one of its probes to the common output terminal of the resistor. Use the other probe to measure the resistance between the output terminal and each of the resistor’s input terminals. Measure the resistance between one pair of terminals at a time.
Of course, to do this, you need to know which terminal is the common terminal (it’s the one directly feeding the fan motor). And you’ll also need to know which of the other terminals is which speed – you can find this information in an online wiring schematic for your vehicle if you know where to look. AutoZone has some great wiring diagrams, and if you can't find them I have the Haynes manual at home with the diagrams. I can snap a photo and share it if needed.
Of course, to do this, you need to know which terminal is the common terminal (it’s the one directly feeding the fan motor). And you’ll also need to know which of the other terminals is which speed – you can find this information in an online wiring schematic for your vehicle if you know where to look. AutoZone has some great wiring diagrams, and if you can't find them I have the Haynes manual at home with the diagrams. I can snap a photo and share it if needed.
Pictures of what that white film is would be helpful. Is it on the contacts themselves or the metal fins (which are called heat sinks). On the contacts, it might be dielectric grease or something similar. On the cooling fins, I'm not sure what that would be and it more than likely shouldn't be there.
I forgot to ask about coolant levels. How are they? If they are low or the thermostat isn't opening, or if you had work done on the cooling system and haven't bled the air out you may have a pocket keeping the hot water from going into the heater core itself.
It also sounds like it could be a bad door actuator, as they are moving funny. Do you get any clicking noises? These actuators are made from cheap plastic and have a tendency to break at the worst possible times.
I forgot to ask about coolant levels. How are they? If they are low or the thermostat isn't opening, or if you had work done on the cooling system and haven't bled the air out you may have a pocket keeping the hot water from going into the heater core itself.
It also sounds like it could be a bad door actuator, as they are moving funny. Do you get any clicking noises? These actuators are made from cheap plastic and have a tendency to break at the worst possible times.
1 - 4 of 8 Posts
