A technician will use it for: Insulation resistance testing - This helps in ascertaining insulation integrity and therefore prevent leakages which can result in injuries. Detection of rotor bar faults. Ascertaining the integrity of the of the motor to determine whether more tests and repairs are necessary. Detections of loose connections and problems in the circuitry in the winding coil. This auto diagnostic repair tool comes with one of these two options: rechargeable batteries or electric chargers.
Attach the leads of the multi-meter to where the electrical wires come into the motor. Again, set it to DC volts and it should read 12 volts. Look for any interrupted voltage caused by a loose connector or corrosion. If there are any loose or corroded connections in the circuit they will disrupt the signal and cause your window to malfunction. Fix the connector or corroded areas. Push any connectors or wiring harnesses together tightly, and clean any corrosion away with a wire brush or similar tool. Test the window again. If your problem was in the circuitry and is now fixed, then your window should freely roll up and down without any restrictions or delays.
Of course, there are plenty of wiring problems an engine can experience and they can be very difficult to locate unless the mechanic is experienced. Analysing electrical problems requires using special equipment combined with mechanic expertise. Today's engines are extremely sophisticated combinations of electronics, electrical wiring, and moving parts and seem like they are half-computer and half-mechanical.
A dirty or clogged engine air filter is more likely to reduce acceleration than fuel economy, according to tests conducted by the EPA. Because filters get dirty gradually over time, you might not notice a small but steady loss of performance until your car is accelerating like a turtle. But if you haven’t changed the filter in a couple of years (or sooner in areas that have a lot of soot in the air), that could be part of the problem.