Service Vehicle Soon Light Help?

Every Once In A Few Days My Service Vehicle Soon Light Comes On? Does Any One Know What Can Be Causing This?
The Car Drives Fine, Nothing Seems Wrong. Wierd Huh?

Any Input Would Be Appreciated. Thanks

Have your exhaust system checked out. This is the most common cause of SES light. It could be any part of the system, Oxygen sensor, catyl. converter, anything.

Have your exhaust system checked out. This is the most common cause of SES light. It could be any part of the system, Oxygen sensor, catyl. converter, anything.

I'd just like to add that they only way to find out what it is that's causing the SES light to come on is to retrieve the diagnostic trouble codes. If you have a code scanner you can do this yourself, but since you are asking on this forum, you probably don't have one so you'll have to take it to the dealership to have them read the trouble code(s).

Every Once In A Few Days My Service Vehicle Soon Light Comes On? Does Any One Know What Can Be Causing This?
The Car Drives Fine, Nothing Seems Wrong. Wierd Huh?

Any Input Would Be Appreciated. Thanks



If you have a NAPA. Auto Zone or National Auto Parts Store Most of them can hook there scanner up to it for free and tell you what the scanner say's is wrong. I hope this helps.

Behind the drivers rear wheel and up inside the rear fender well there is a black box with two or three vacuum lines attached to it. It is part of the emissions system and they are often the cause of "ghost" ses lights coming on. It may be leakig and will need replacement if so. It is available from the dealer for about $65.

Behind the drivers rear wheel and up inside the rear fender well there is a black box with two or three vacuum lines attached to it. It is part of the emissions system and they are often the cause of "ghost" ses lights coming on. It may be leakig and will need replacement if so. It is available from the dealer for about $65.

Could this problem also cause an engine misfire condition? My Impala just crossed 80,000 and I just replaced my catalytic converter because it was stopped up. The only trouble code that keeps occurring is "Catalyst system below efficiency threshold" (Code 420). The check engine light flashes to indicate a misfire and I feel a definate misfire when accelerating (only when rolling on the throttle at about 1500 rpm or under WOT at 3500-4000 rpm. Previously, it threw a code for a cylinder #1 misfire (before the cat trouble) amd I traced that back to a malfunctioning coil pack. ( I also replaced this spark plug twice and the wire is in good condition) I'm also checking out the fuel injectors and Oxy sensors. Any help would be appreciated.

On my Mesage Center the Service Vehicle Soon light comes on followed by Security Light and followed by Battery red light. I've replaced the alternator but is doing the same thing. Can anybody help me with this ? Please !!

voltage regulator????

Could this problem also cause an engine misfire condition? My Impala just crossed 80,000 and I just replaced my catalytic converter because it was stopped up. The only trouble code that keeps occurring is "Catalyst system below efficiency threshold" (Code 420). The check engine light flashes to indicate a misfire and I feel a definate misfire when accelerating (only when rolling on the throttle at about 1500 rpm or under WOT at 3500-4000 rpm. Previously, it threw a code for a cylinder #1 misfire (before the cat trouble) amd I traced that back to a malfunctioning coil pack. ( I also replaced this spark plug twice and the wire is in good condition) I'm also checking out the fuel injectors and Oxy sensors. Any help would be appreciated.
Were you also getting the smell of "rotten eggs" from the catalytic converter? The computer says that I have a misfire on the #3 cylinder. The shop said that its a computer problem, we also replaced the coil,wires and plugs. Haven't had it to the dealership yet.

check the oxygen sensor behind the catalytic converter. It could be sending the code. I just had my converter switched out with a Hi-Po converter adn the car runs great. I was having a terrible hesitation, no power and terrible gas mileage.

Is there anyway to read the codes without a reader? I know a lot of vehicles can do this.

Could this problem also cause an engine misfire condition? My Impala just crossed 80,000 and I just replaced my catalytic converter because it was stopped up. The only trouble code that keeps occurring is "Catalyst system below efficiency threshold" (Code 420). The check engine light flashes to indicate a misfire and I feel a definate misfire when accelerating (only when rolling on the throttle at about 1500 rpm or under WOT at 3500-4000 rpm. Previously, it threw a code for a cylinder #1 misfire (before the cat trouble) amd I traced that back to a malfunctioning coil pack. ( I also replaced this spark plug twice and the wire is in good condition) I'm also checking out the fuel injectors and Oxy sensors. Any help would be appreciated.

I was getting this same code after I replaced my cat converter. The dealership told me it was because I replaced it with an aftermarket converter that wasn't as big as the stock chevy part and it causes the oxygen senor to think there is a problem. Did you replace it with the Chevy part or an aftermarket?