My battery light is on.

ANSWER : Hi. If the Battery Light is on, this an indication that either the battery is bad, the alternator is not charging properly, or both of them are bad. Low battery voltage will cause the car to do abnormal things like have no headlights. There are other things that can cause headlights to not work as well, for example, a blown fuse, broken headlight relay, or, the most common cause, blown headlight bulbs.

I suggest you have a certified technician, such as one from YourMechanic, come to your location to determine why the Battery Light is on and suggest the necessary repairs.

ANSWER : As you may yourself have seen, there are many reports of this fault with the Civic, that is a battery or alternator is replaced only to have the warning light fail to extinguish despite checking every conceivable electrical possibility. Your only recourse is to have a certified mechanic go through that exercise with your car and that involves first attempting to "re-set" the light. If the warning light returns, the alternator output has to be carefully measured both loaded and unloaded. All terminal connections have to be verified including all grounds. Fuses have to be checked for integrity (continuity) and the possibility of shorts, in for example dash wiring, has to be checked. To request this repair, simply request an electrical components diagnostic and the responding certified mechanic will seek a resolution to this.

ANSWER : Hi, thanks for writing in. This may be a sign of a failing starter relay. The starter relay is a small unit near the starter that directs power to the starter from the battery. When this fails, it may cause a clicking sound and will not allow the starter to engage the flywheel when you turn the key. I would suggest having a professional from YourMechanic come to your home to diagnose your starting issue to determine the solution to get you back on the road.

ANSWER : Batteries can die due to faults in the charging system so ideally a suspected "faulty" battery should be load tested before a decision is made to condemn it. The only exception to this rule is if the battery is already clearly "old" (greater than 5 years) but even then once you put a new battery in, as a replacement for a "dead" battery, you have to comprehensively check out the charging system. Diagnostic Trouble Code P0460 will result in disruption of the dashboard fuel gauge’s ability to accurately report your tank’s fuel levels. The fuel gauge readings may be erratic, or read somewhere off scale. Vehicles equipped with a low fuel warning light feature may also suffer from erratic low fuel warnings in the event of a code P0460. Unless the P0460 code has been reported alongside other trouble code, all of the vehicle’s essential systems should otherwise function normally. I would recommend that you request a check engine light diagnostic to first resolve the fault causing the P0460 code to set. The check gas cap light warning light could be due a faulty gas cap and/or small leaks in the EVAP system.

ANSWER : Hello, thank you for writing in. The vehicle does utilize a lot of the same sensors for these systems. Are there any other codes that are coming up when this code appears? If so you will want to take these into consideration when processing the repair and making a diagnosis. The module may be bad, and replacing it should fix the problem. The lights should turn off once the main computer recognizes the new module and the sensors sync up. If you believe the sensors need to be cleaned you may do so. Do as minimal as possible to make sure you are not damaging the sensor or disrupting the wiring inside. A bad connection would make the lights stay on. With so many lights that are effected by the module being illuminated, the module is likely bad or does not have a connection. Check the connection first and then resort to replacing the unit. For more help with these electrical tests, contact our service department.

ANSWER : You may have a failing voltage regulator that could be allowing the alternator to supply too much or too little amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

ANSWER : The alternator on this vehicle is computer controlled and if the alternator is not communicating to the computer then it may default to a set charging rate that will show up as good when testing using standard methods. The computer and charging system needs to be tested using a scanner that is compatible that can check and test charging rates. You most likely do have a bad alternator on the car.

ANSWER : Hi there. In many cases, when you have electrical problems like you’re describing, it’s caused by multiple electrical component failure. It’s likely that a few electrical relays are not working; especially if you have systems that utilize the same components (such as your brake light and tail lights). I would recommend having a professional mobile mechanic come to your location to complete an electrical problems inspection first, so they can pinpoint what is damaged and recommend the right repairs.