Skip the auto shop - Our mechanics make house calls

Q: key won't start engine

asked by on

This past week I have been having trouble starting the car. It was struggling while turning the key to start. Then the other day I tried and it wouldn't even unlock with the remote. I tried the blade key, tried to turn it and it turned. The dashboard lit up very briefly, then it died. Now I can't get the key to turn assuming the infrared isn't turning on to see the key. I tried the jumper cables with my friends car and still couldn't turn the key. The battery is not more than a year old and the same thing happened a year ago. All we did was replace the battery. Can a battery be too dead to jump? Do I need to go buy a battery charger and charge it overnight and try turning the key again tomorrow? If not, can I go buy a new battery use cables to charge the battery as it sits in the car and then return the battery?

A: It is possible that you could have one of t...

It is possible that you could have one of two issues. You could be experiencing a bad alternator problem that is causing your battery to be drained and become faulty well before it should be. In this case, I would recommend having an electrical systems check to determine if the alternator is performing as it should.

This test may involve the use of a digital multimeter to first test the battery for proper voltage. If the battery does not have proper voltage it may need to be charged or replaced in order to start the vehicle.

Once the vehicle is started, the alternator output can then be tested with the digital multimeter. Another way to test the alternator would be on a machine that is available at most auto parts stores. This test would require the removal of the alternator from the vehicle.

The other possibility is that you could be experiencing a parasitic draw. A parasitic draw is when something electronic is drawing power from the battery while the engine is off. This would be something other than the alarm system and certain memory functions that are low draw features and are supposed to be drawing power when the vehicle is off.

I would recommend having this issue checked out by qualified technician who can performs these checks and pinpoint your starting issue firsthand.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Sticking Ignition Key

It sounds like your Mercedes is having issues with these keys since they are on back order. I can only suggest maybe checking with a local vehicle locksmith. They may be able to make a key that can work for...

Q: 1997 s500 oil light on and engine makes a ticking noise at idle.. /code p0115

It looks like you have separate issues. Code P0115 has to do with the coolant temperature circuit. This code can be set due do a thermostat that is not opening or closing fully or even a bad coolant temperature sensor....

Q: My car is overheating quickly - 2000 Lincoln LS

Hi and thanks for contacting YourMechanic. Check to see if the electric fan is coming on when at idle. If the fan is not coming on, check the fuse box for any blown fuses. If all of the fuses are...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...