Here's what you should check:
* Blower Motor Resistor: This is the most common cause. It's a relatively inexpensive part and usually located behind the glove box or under the dash. You can find diagrams and videos online showing its location and how to replace it for a 2002 Venture. Replacing this is often a DIY fix, but if you're not comfortable working on your car, take it to a mechanic.
* Blower Motor: While less likely, a failing blower motor can sometimes only run at full speed before completely dying. This is more expensive to replace than the resistor.
* Wiring and Connections: Check the wiring harness leading to the blower motor and resistor for any loose connections, corrosion, or broken wires. A simple loose connection could be the culprit.
* Fuse: Though less probable given the high-speed functionality, a blown fuse could be limiting the lower speeds. Check your owner's manual to locate the correct fuse for the blower motor.
Before starting any work:
* Disconnect the negative battery terminal. This is crucial for safety to prevent electrical shocks.
* Consult a repair manual or online resources specific to your 2002 Chevrolet Venture. This will give you detailed diagrams and instructions.
If you're not comfortable tackling this yourself, taking your Venture to a qualified mechanic is the safest option. They can diagnose the problem accurately and perform the necessary repair.
