Scion TC Parts And Scion TC Accessories
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Normally, when the lights and other electrical parts don\'t work in the Scion tC, the first thing that comes to mind is a busted battery. But what happens when you swap to a new battery and the car still goes dark? In this case, it might be a deeper problem with the car alternator.
Unlike a malfunctioning car battery, a broken alternator is a more serious concern. Attached to the engine via a drive belt, the alternator is actually the one responsible for providing electricity to your Scion; the battery just stores the energy the alternator makes. Normally the alternator can last the entire life of the Scion tC, but poor maintenance, exposure to extreme heat and cold, being submerged in water, and other factors can cause the alternator to fail.
If you suspect your Scion\'s alternator is the cause of the problem, the first step you need to take is to confirm it. To do this, you will need to determine the battery\'s engine-off voltage using a multimeter. Set the multimeter knob to 50 volts, touch the red lead to the positive battery terminal and touch the black lead to the negative terminal. Take note of the voltage reading; as a rule of thumb, a properly functioning alternator should give a reading of 13.5 to 14.5 volts. If the reading does not reach that high, turn on the headlights and blower motor and rev the engine until it reaches around 2,000 rpm. If the reading still fails to reach that mark, the alternator may be faulty.
Make sure the battery is fully charged before starting the multimeter test. Anything might result in an inaccurate reading with the multimeter.
If the battery does provide the correct voltage reading, switch the multimeter to its lowest AC setting and reconnect the test leads to their respective sides in the battery. Switch on the engine again and take note of the reading. If the multimeter displays an increase in AC voltage, the alternator has a bad diode and must be replaced.
With the engine shut off and cold to the touch, disconnect the battery cables from the battery. Remove the wires and cables from the back of the alternator and remove the alternator drive belt. Once the belt is out of the way, loosen the alternator drive bolts. We recommend using an electric or air-powered ratchet for this, as the retaining bolts are quite long and you\'ll spend a lot of time cranking them by hand. Carefully pull out and mark the bolts and take out the alternator itself. Simply do the entire process in reverse to install the new alternator.
Ideally, you should buy a brand new alternator to replace the one in your Scion. While rebuilt or refurbished alternators are cheaper, they may not last as long and have shorter or no warranty compared to a brand new unit. And to save money, we recommend buying alternators online. Online retailers can sell replacement brand new alternators cheaper than those offered by brick-and-mortar ones thanks to lower overhead costs.