Symptoms suggesting a bad relay solenoid:
* Clicking sound: You'll hear a distinct clicking sound, often fast and repetitive, coming from the relay solenoid itself (located near the battery or starter). This is the solenoid trying to engage but failing. The starter might not even attempt to turn.
* No cranking: The engine won't crank at all, or only makes a weak clicking sound.
* Intermittent operation: Sometimes it works, sometimes it doesn't. This is a classic sign of a failing solenoid's internal contacts.
* Directly testing the solenoid: If you have some electrical knowledge and are comfortable working with car batteries, you can use a jumper wire to bypass the solenoid and directly apply power to the starter. If the starter spins, the solenoid is likely at fault. Caution: Be extremely careful when working with car batteries and high amperage circuits.
Symptoms suggesting a bad starter:
* Slow cranking: The engine cranks slowly or struggles to turn over. This indicates the starter motor itself is weak or failing.
* Grinding noise: A grinding noise during cranking often points to a problem with the starter's gear meshing with the flywheel.
* No cranking but no clicking: Silence upon turning the key is possible if the starter motor is completely dead.
* Intermittent operation (but different from solenoid): The starter might crank weakly sometimes and not at all other times, but this will typically be related to the motor’s internal components failing, not simply a bad connection.
Distinguishing features:
* Location of the sound: The relay solenoid's click will be localized near the solenoid itself. A starter motor problem will generate sound closer to the engine block (where the starter is mounted).
* Nature of the sound: A solenoid click is a sharp, clean, electrical clicking. Starter motor problems often involve slower, grinding, or whirring noises.
Troubleshooting Steps:
1. Listen carefully: Pay close attention to the sound the vehicle makes when you turn the key. Is it a rapid clicking (solenoid), a grinding noise (starter), or just silence?
2. Check the battery: A weak battery can mimic the symptoms of both a bad solenoid and starter. Make sure the battery terminals are clean and tight and the battery voltage is adequate.
3. Inspect wiring and connections: Check all wiring connections to the battery, solenoid, and starter for corrosion or looseness.
4. Tap the solenoid: Sometimes a gentle tap on the solenoid with a hammer (while wearing safety glasses) can temporarily restore contact, pointing to a failing solenoid. This is a temporary fix, and the solenoid should be replaced.
5. Test the solenoid (advanced): Use a multimeter or jumper wires to test the solenoid's continuity. Do this only if you're experienced with automotive electrical systems.
6. Have it professionally diagnosed: If you're uncomfortable performing electrical tests, take your Windstar to a qualified mechanic for diagnosis. They have the tools and expertise to pinpoint the problem accurately.
In short, while both a faulty solenoid and starter can prevent your Windstar from starting, the *sound*, *location of the sound*, and *nature of the engine cranking attempts* will help you differentiate the cause. Don't hesitate to seek professional help if you're not comfortable working on your vehicle's electrical system.
