My car won't start. We've changed the starter and tried many batteries. When we turn the key the volts on the battery drop from 12 to 7 or 8. My car has an automatic transmission. I know it is definitely now the battery. We have tried 3 batteries and none work.
Hi there. From the description you have provided, your vehicle’s no crank appears to be more than a battery or starter problem. It could be poor terminal connections at the battery and/or the other end of the battery cables. Check the voltage at the terminal ends. If you are putting your voltmeter probes on the battery posts and seeing 7 or 8 volts while turning the key to the crank position.
There is excessive draw being placed on the replacement battery and replacement starter. This would be an indication the engine is locked-up. You could try turning the engine by hand. If it won’t turn over, remove the spark plugs and again attempt to turn over by hand. If it still won’t turn over, then the engine has seized. If you would like some help getting this all scoped out, a certified professional from YourMechanic can come to your car’s location to diagnose the starting issue and have this taken care of.
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