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.
1992 Lexus ES 300 AutomaticFACTORY OEM SERVICE PROCEDURE
Using An Ammeter With A Current-Measuring Probe
- Remove the master switch with connector connected.
- Attach a current measuring probe to terminal 8 of the wire harness. See Fig 1.
- Turn the ignition switch ON and set the power window switch in the down position.
- As the window goes down, check that the current flow is approximately 7 A. See Fig 2.
- Check that the current increases up to approximately 14.5 A or more when the window stops going down. If operation is not as specified, replace the master switch
NOTE:
The circuit breaker opens some 4-40 seconds after the window stops going down, so that a check must be made before the circuit breaker operates.
Factory Service Tools
Use the Manual With the Right Hardware
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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.