Skip the auto shop - Our mechanics make house calls

Q: The car is not starting after I changed the aux cable in the stereo.

asked by on

After changing the stereo aux cable, the car is not starting. When I try to start the car, I hear loud cracking noise. Then, door lock doesn't work, some lights turn on automatically. The door lock works and the light turns off after I remove one of the terminal of the battery. If I just turn the keys on, after some seconds, the hazard light, headlight and dashboard lights starts blinking rapidly. After a while everything turns off. The same thing happens again if I turn of the engine and turn on again. I tried to find the short using multimeter. I disconnected the positive terminal and connected one end of the multimeter to positive terminal and another end to the removed positive wire of the battery. The short test showed 11.4 V. Then I removed fuses one at a time. But, the voltage reading remained same. Then, I removed all fuses and still test showed same voltage. Please provide me some suggestions. I am being totally helpless.
My car has a manual transmission.

A: To begin with, the lighting and door lock m...

To begin with, the lighting and door lock modules are very sensitive to low battery voltage. Once the battery voltage drops, they can start to do crazy things, making the car appear haunted. Door locks and windows may start to operate at random even while the car is parked. So, first you want to be sure the battery is fully charged. Second, you need to re-visit that stereo installation.

Check that all the connections are in accord with the factory system. The factory radio has a CAN (Control Area Network) line going to it. This is the line that all the modules use to communicate with each other. Since it tests at 12 Volts with a meter, many accessory installers mistakenly hook the CAN line up to an accessory radio. When this happens, the car can really exhibit some weird symptoms.

The CAN Line can be distinguished from the rest of the electrical system because it is a twisted pair of wires. It should not be hooked up to an aftermarket radio. Plugging the CAN line in where it should not be can damage one or more of the car’s control modules.

Beyond that, I suggest you get professional help. A certified mechanic, such as one from YourMechanic, can come to your location to inspect for electrical problems and suggest needed repairs.

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: Why car is sluggish starting?

Hello, There are many different things that could potentially contribute to your car starting sluggishly, however I would recommend starting with checking the most common things like the starter, starter relay and starter solenoid. These are things that may not...

Q: Car won't crank or start with ignition - Audi A3

Hi there. From the description you have given, the problem of your vehicle not cranking with the key and gear indicator (P) flashing. This leads me to believe, there is a problem with the transmission position sensor. Not recognizing the...

Q: Popping noise when accelerating

Hi. The noise will have to be inspected to initiate a diagnosis of what the problem might be. If the noise only occurs when the body of the vehicle shifts its weight, then it is either the suspension, body mount,...

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...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.