Skip the auto shop - Our mechanics make house calls

Q: Car won't start, would not start with boost. Ran fine when I bought it. It sat for two weeks and the alarm was left on.

asked by on

Just bought my Mazda off girl in to. Drove home to Cambridge and parked it. It sat for two weeks with alarm left on. Went to start it up it was dead. Gave it a boost and it didn't start. Nothing comes on. Could my alarm made the battery dead?

A: Hello. The short answer is yes - the alarm ...

Hello. The short answer is yes - the alarm can drain the battery in 2 weeks. It is also possible that something else is draining the battery while the car is turned off, and all electrical systems should be passive. This problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain, then one at a time, remove each fuse. Check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. Further diagnosis is then required for the electrical components on that fuse to identify the component pulling current. A professional mechanic, like one from YourMechanic, can diagnose the starting problem and perform any procedures or repairs needed to have this resolved.

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・Fair and transparent pricing

Get a quote

What others are asking

Q: The car cannot be started randomly

It sounds like your ignition switch may have an intermittent failure. I would recommend having your ignition coil tested by a certified technician and replaced if necessary to see if that will fix the issue. Considering that this issue has...

Q: Turn off theft lock Ford Escape 2001

If you still have one of the old programed keys from the other steering column all you have to do is hold it near the ignition when you turn on the key to see if it starts this way. If...

Q: Problems with various electrical functions after replacing the battery....

Hello, thank you for writing in. The vehicle is likely having an issue with the charging system. This may mean there is an issue with the alternator, or the connections to the battery. You will want to do a full...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...