GM GENUINE PARTS blower motor resistor for HVAC — Part 15-8788 / 15039098, OE direct-fit restores multi-speed fan control

This blower motor resistor is an original-equipment (OE) replacement part engineered and validated by General Motors to match the fit, function, and durability of the factory-installed component. It supplies stepped voltage drops to the blower motor so the cabin fan can operate at multiple speeds. If your HVAC system runs only on one speed or not at all, a failed resistor is a common cause and this GM Genuine Parts unit is designed to provide a direct-fit repair.

How does this resistor restore HVAC fan speed?

The resistor modulates current to the blower motor using several discrete resistance paths so the fan can run at different speeds. Replacing a faulty resistor with the correct OE part ensures those voltage steps are restored and the original blower control behavior returns.

• Provides stepped voltage drops for multiple fan speeds
• Direct-fit for specified GM models — no modification required
• Replaces worn or open resistor coils that cause speed loss

What makes this a dependable GM Genuine Parts option?

GM Genuine Parts are engineered, tested, and recommended by General Motors, so they meet the automaker’s standards for reliability and durability. This resistor follows GM OE specifications for dimensions, connector locations, and electrical characteristics to ensure proper operation with factory controls.

• Manufactured to GM OE specification for fit, form, and function
• Backed by General Motors validation and quality control
• Often previously listed under ACDelco GM Original Equipment (OE)

How do I know this is the right part for my vehicle?

Confirm compatibility by checking your vehicle’s year, make, and model against part number 15-8788 or GM 15039098. Visual comparison of the resistor’s connector and mounting points to the old part helps ensure a match before installation.

• Part numbers: GM Genuine Parts 15-8788 and 15039098
• Verify fitment against your vehicle’s VIN or parts catalog
• Compare connector shape and mounting location to existing resistor

What should I expect during replacement and performance after installation?

Installation is typically straightforward for someone with basic automotive experience: disconnect the battery, remove the HVAC cover or glove box as required, unplug the old resistor, and mount the new unit. Once installed, the blower should regain its full range of speeds and operate without intermittent failures associated with a damaged resistor.

• Restores blower speed control caused by a failed resistor
• GM-recommended replacement for original factory component
• Quality and durability consistent with GM OE expectations

Who is this for? This GM Genuine Parts 15-8788 (15039098) blower motor resistor is aimed at GM owners, independent mechanics, and repair shops seeking an OEM-quality replacement for HVAC fan-speed issues. It’s a practical choice if your vehicle’s blower runs only at one speed, fails intermittently, or if you want a factory-validated part to maintain original performance and fit. Always verify compatibility with your specific model year and consult a qualified technician if you’re unsure about installation.