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Why does the alternator light come on when you shut the key off?
Wiki User
∙ 15y ago
The alternator light goes out on starting the engine when both the ignition source, and alternator are producing positive voltage. When the ignition switch is turned off, the engine, and of course, alternator are still turning momentarily. The alternator is then still producing positive voltage, while the 'off' ignition switch has assumed a negative state, creating a closed + - circuit, allowing the lamp to light. This is a very normal state, and has occurred for many decades, even back to the days of cars running generators, prior to the alternator. Absolutely nothing to fear.
Wiki User
∙ 15y ago
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Why doesn't the alternator light come on when key is turned to on?
Could be a bad bulb Could be a bad voltage regulator (circuit not opening on engine shut down)
Why is battery light on after key removed on my Porsche 944?
bad alternator
Why does battery not charge with new alternator?
When alternator went out, it could have taken out a fuse if the alternator shorted. The main battery cable to the alternator is not fused, but in your panel you should find an ALT fuse. most alternators have two to three small wires that are in a pigtail that plug into the alternator. these small wires are fused. if your car can't pass current through an open fuse. then there is nothing to essentially tell the alternator to turn on. another thing to check, is whether the battery light comes on. if you turn the key to the forward position, without trying to strart the engine, your prestart lights should all light up. this is a system precheck before the engine starts. the battery light should come on at this point. if the light doesn't come on that is an indication of a fuse being blown. in a lot of vehicles, from the seventies to the late nineties, the charge light, or battery light has to work in order for the alternator to work. if the bulb in the dash(which is behind the battery light) burns out, your alternator will not receive power to turn on and work. again, newer vehicles do not have a light circuit that it relies on for the alternator to function. keep in mind, your battery light should have come on and been on the entire time the old alternator was in the vehicle. if it wasn't on, then this is something to pursue further.
What would cause the alternator warning light to come on in a 1979 Chevy Malibu?
Its telling you that for some reason the battery is not charging. Possible cause are: poor or dirty cable connections at the battery posts, bad cables, bad battery. It is also possible that the brushes in your alternator are bad but, the fact that you are getting a light usually indicates the problem is with the battery or cables. For some reason on a GM alternator when the internal regulator in the alternator fails you don't get a light. The only indication you get is that when you turn on the key the battery light doesn't come on. So it is probably not the alternator. Check for corrosion around the battery cables where they connect to the battery. That is most likely the problem. If you have the type that screw into the side of the battery, they may have just worked loose. Good luck
What would cause the battery light to come on and go off several times and it says security?
When it says security it means the the chip in your key has gone bad, or the key dont have a chip in it, and u it wont let u doing anything, you have to have the chipped key I am thinking this is going to be a bad alternator, or a battery that has a dead cell. You can get your alternator checked while on the car at Autozone for free. That would be my sugestion as a place to start.
Why does the maintenance light come on in a 1997 Honda Civic?
its not a light,reset with your key
What other than battery or cables can cause a 1997 Mark 8 to intermittently completely shut down so the seat does not move the light does not come on and the key doesn't work?
the ignition swtich...(electrical portion behind the key) could be the cause.. dave
You have a1994 century buick 4 cylinder after replaces alternator belt alternator and battery it still want stay charged?
Okay the first thing I want you to do is turn the key on and observe the warning lights. Does the battery light come on? If not the voltage regulator in that alternator is bad. Assuming you have a good alternator and a good battery You may have a voltage drop somewhere. The most common is an underhood light or trunk light that doesn't go out when you drop the hood or close the trunk. Others may include a door switch or possibly a short somewhere. Good luck.
No interior lights and headlights won't shut off until you turn key off on 2003 S10?
what do you mean interior lights dash lighs or dome light 1993 i believe have the sensor when it gets dark lighs come on automatically and dont shut off unless vehicle is off
Is the check engine light supose to come on when you turn the key in a 98 Chevy blazer?
At key on it should come on for a couple second "bulb check".
How do you stop the door chime from chiming when the door is shut and the key is removed from the ignitiion of a 2001 Pontiac Grand AM SE?
There are noises and lights that tell a driver there is something wrong with a car. The chiming when the door is shut and the key is removed, usually indicates that a light may be on.
Why does your Chrysler 300 shut off when this little red light is on dash. What is that little ball like light?
That indicates that there is a malfunction in the theft alarm system or the "chipped" key system. Chrysler calls it Sentry key immobilizer (SKIM)
