When the car won't start, most people quickly blame the starter. That's not always the problem, but things do go wrong with the starter and its solenoid. To quickly diagnose and then get it repaired, some simple steps can tell you whether or not the starter is to blame with just a few minutes under the hood.
How the Starter Works
Your vehicle's starting system is pretty simple. They key switch tells the circuit between the battery and the solenoid to open. The solenoid then cranks up the power and causes the starter motor to engage, turning the engine over until it fires and begins running on its own (or you let go of the key). It's a simple process that can have a surprising number of details go wrong.
Diagnosing a Starter Problem
The first thing to do if your vehicle won't start is note the sounds it's making as you turn the key. If it makes a ìclickingî but nothing more, then your problem could be different than if it makes a grinding noise instead.
Clicking sound, but no turnover.
This means either the solenoid is not getting enough power or it's failing to send power to the starter. First, test the battery with an Ohm meter. If it does not have at least 10 volts, recharge or replace it with a fully charged battery and try again. This is actually the most common starting problem in a vehicle.
If recharging the battery doesn't work, then there is a problem either in the connection from the battery to the solenoid or the solenoid itself is not transferring power to the starter. Test the connections from the positive battery terminal to the solenoid (it will be a straight-through, thick cable). Be sure it's transferring the minimum cranking amps your vehicle's manual recommends. Make sure there are no breaks or frays in the wiring and that all connections are solid, clean, and secure. Remove and clean if you have any doubts. Then try to another start.
If no luck, there's a good chance the solenoid has blown. Remove and replace. Often it is integrated with the starter, so both require replacement.
Scratching, grinding sound, no or intermittent turnover.
In this case, the problem is your starter's gear teeth are not connecting with the ring gear. Check that it's mounting bolts are secure and that there are no cracks in the housing of the starter or the transmission. Remove and replace and be sure to inspect the ring gear as well.
Other Common Starter Problems
In modern vehicles, the most common starter problems are usually electronic. Often, the key switch fails to complete the circuit for the battery to the solenoid or the vehicle's anti-theft device blocks the circuit as it malfunctions and assumes the car is being stolen. Specialized knowledge and tools are required to repair these issues.
Vehicles can be taken to an automotive repair shop, or an owner may be able to perform diagnostics and repair or replacement. Online service manuals can be purchased on this site.
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