Skip the auto shop - Our mechanics make house calls

Q: new stereo unit not working, interior lights and fuel level not working or showing up

asked by on

So I installed a new Sony stereo unit, we Had to remove the older after market head unit, after it was removed we had to re wire the cables to the new head unit and I'm confident that we re wired the colour coded wires correctly. I disconnected the battery first before I went to remove the head unit, but after installing the new unit it doesnt turn on we also found out that non of her interior lights are working now and the fuel level isnt showing up anymore? i reading some similar problems and some say that it could be the battery ground not hooked up properly or that head unit cables could be doing this, please I need your help Thanks Kennedy

My car has 188889 miles.
My car has an automatic transmission.

A: Following the colors of the wires is not a ...

Following the colors of the wires is not a full proof method to be sure you have made the correct connections. You clearly have some connections that are not correct. The only way to figure out what is what in the wiring harness is to find yourself a wiring diagram for the car and hopefully you have a detailed wiring diagram for the stereo. With the two of these, disregard the wire colors and confirm the power connections go to power connections, grounds go to grounds etc. This can be time consuming so give yourself time to study the diagrams.

When wrong connections are made, the symptoms that follow are always going to be random and unpredictable, so don’t worry yourself to much with what is happening with the car. First you need to start with the correct connections. I recommend starting with a few wires at at time. First power and ground then maybe speaker wires and antenna. If you make these connections and the stereo begins to work, you will know your on the right track. Make one connection at a time and observe if there are any problems that occur. If a problem occurs, you can isolate it to the last connection you made.

The use of a test light to confirm power with the key on or off is valuable with such an installation. Be patient and I’m sure you can figure this out.

If you find that this is more than you bargained for, consider YourMechanic, as a certified technician can help you sort out the issue with your electrical components.

Good luck!

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

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: How do I select the radio band?

To select the radio band you want to listen to, press the AM/FM button. The sound system will then cycle between FM1, FM2, and AM.

Q: Stalling misfiring CEL

Hello, thanks for writing in about your 2003 Jeep TJ. Yes a clogged catalytic converter can cause the O2 sensors to go bad prematurely. I suggest replacing the clogged catalytic converter before installing the new O2 sensors. I can't say...

Q: Car is heating up after 100kms run

Hi there. The condenser is not likely to cause an overheating issue unless, the front side is plugged with debris, restricting airflow to the radiator. I have seen debris in between the condenser and radiator restrict airflow. With only 40,000...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
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.