How can I tell if I need a new starter?

Having problems starting your car? Does the engine crank slowly or not at all? Here are a few tips on checking the condition of your starting system. First, check the condition of your battery. This is the primary source of your starting system. If the battery is fully charged and has the correct amperage output, the next item to check is the wiring for the starting system.

Inspect the battery cables and terminals for green or white corrosion, and clean as neccessary. If corrosion is present, this will cause connection problems in your electrical system. Also, check to make sure the battery cables are the correct gauge, or diameter. If a battery cable is too small, current, or amps, will not flow readily to the parts needing the energy. Using a digital volt/ohm meter, or DVOM, check to see how much resistance is in the wire. Resistance will reduce the amperage flowing through the wire.

Next, perform a voltage drop test on the wiring. Placing the positive lead of your DVOM on the positive battery terminal and the negative lead on the end of the starter wire on the solenoid, there should be no more than 0.2 volts. Once this is measured, measure the voltage going to the starter. This should be about 12 volts, DC, or direct current. If the proper voltage is reaching the starter, then there is a problem with the inner workings of the solenoid, or the starter itself is bad.

The best way to check for a bad solenoid is to check the amperage draw on the starter. To do this, place an amperage probe on the starter wire and try to crank the engine. If the amperage load is unusually high, the solenoid is damaged. In most cases, the solenoid is built into the starter, so they are replaced as one item. If the starter still cranks the engine enough to start, but the amperage draw is high, it is recommended to replace the starter assembly. A large amperage draw from the starter can lessen the effectiveness of your battery, in turn putting more strain on the alternator, which charges the battery as you drive. Simply by replacing the starter, the entire electrical system’s life is prolonged, saving money and keeping your car on the road.

Copyright © Smitty’s Auto Service, Inc. 09/30/2010

These repair tips are provided by Smitty’s Auto Service, however we accept no responsibility for repairs you make via these tech tips as they may not be appropriate for your vehicle, so use them at your own risk. Please seek advice from a professional mechanic for all repair problems or contact Smitty’s Auto Service for more information:
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