Year, make and model? How does the connector and wiring look? Any signs of melted plastic in the connector? Any discoloration of the wires? Pull back the wire loom on the leads to the resistor and inspect wires. Check amp draw on blower motor. Is the resistor getting moisture on it?

 

the HVAC blower motor and the motor resistor changed it .

 

bitlife said:
Hello all, my fan resistor keeps flowing out and I can't figure out why. Any thoughts?

The most common reason for repeated fan resistor failure is an electrical overload. The fan resistor is designed to handle a specific amount of current, and if the fan motor or wiring is faulty, it can draw more current than the resistor can handle, causing it to burn out. Check the fan motor and wiring for any signs of damage, corrosion, or loose connections.

 

also the rodent nest inside the blower motor !!!!!!!!!!!!

 

The biggest reason the resistor assembly burns up is because the wiring and the connectors are not big enough.
The connector starts to burn and overheats, then the heat causes the wires to burn off.

When you buy a new resistor, you should also replace the wire harness at the same time.

 

Year, make and model? How does the connector and wiring look? Any signs of melted plastic in the connector? Any discoloration of the wires? Pull back the wire loom on the leads to the resistor and inspect wires. Check amp draw on blower motor. Is the resistor getting moisture on it?

07 1500 Classic, 50k miles. Everything looks good, no breaks, no melted plastic, no discoloration. Idk how to check the amp draw. Otherwise everything looks good.

The biggest reason the resistor assembly burns up is because the wiring and the connectors are not big enough.
The connector starts to burn and overheats, then the heat causes the wires to burn off.

When you buy a new resistor, you should also replace the wire harness at the same time.

Thank you I'll look into that.

 

07 1500 Classic, 50k miles. Everything looks good, no breaks, no melted plastic, no discoloration. Idk how to check the amp draw. Otherwise everything looks good.



Thank you I'll look into that.

Just look at the connector the resistor assembly plugs into

 

More than likely the culprit is the fan drawing too much amperage. Most aftermarket fan and resistor connectors/ pigtails have 10 gauge wires in them. You can put an amperage clamp around the hot wire for the fan to get the amperage draw. At the shop I work at ,we do about 3 a month.

 

That is the reason the contacts in the connector overheat and "burn", the fan draws more current than the factory connector and the wiring are designed to handle. They overheat and they burn.

Actually, when everything is new and clean, the fan will draw more current than is drawn when the problem occurs. When the connector contacts get dirty/burned there is a resistive connection and the resistance increases the load, reducing the current flow.

You didn't say what you do, at your shop, to fix the problem.

 

Purchase some DeoxIT and remove the connector/s and spray them with it. DeoxIT D-Series page with shop - CAIG