Q: vehicle won't turn on or start.

asked by on December 25, 2016

the vehicle started by taking slightly longer to start then later a check engine light came up for crank position sensor and was replaced by Mercedes benz 4 months ago and at the time I complained about the slow start and they said they checked the starter and it was good. infact they say all was goo except I need to replace gaskets as it had started to leak. the slow start kept getting worst and vehicle kept taking longer and longer to start until just wont start at all 5 days ago. head lights come on but nothing happens when I turn the keys. I just replaced the fuel filter and pump two days ago but still the same. any help will be greatly appreciated.

My car has 105000 miles.
My car has an automatic transmission.

Hi there. Check the battery and see if it has a full charge. If the battery has a full charge of 12.6 volts, then put a load tester on the battery and check to see if the battery will hold a load at the minimum or 11.5 volts for 30 seconds. If the battery drops lower than 11.5 volts during the load test, then the battery needs replaced. If the battery is good but had to be charged, then check the alternator (when you can get the engine to start) and make sure that its functioning and charging the battery. There should be a voltage of 13.5 to 14.7. Also, turn on the high beams and operate all of the power windows at the same time with the engine at 2,000 rpm and see if the lights dim. If the lights dim, then the alternator is not producing enough amperage for what the vehicle needs. Then the alternator would need replaced. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with your engine not starting.

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