Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Power Window Relay Inspection
Perform this test when directed in the diagnostic pinpoint tests.
- Measure resistance between terminal 85 and terminals 86, 87, 87a and 30. If resistance is 5 ohms or less between terminal 85 and any other terminal, replace the relay. If resistance is greater than 5 ohms, go to step 2.
- Use two jumper wires to connect terminals 86 and 30 directly to the positive battery terminal. Measure voltage at terminal 87a. If there is no battery voltage, replace the relay. If there is battery voltage, go to step 3.
- Connect a third jumper wire to terminal 85 and a known good ground. Measure voltage at terminal 87. If there is no battery voltage, replace the relay.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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