Long story here, but I have been trying to find solution for years. I have read a few short answers, here is my long one. In short replace ignition cylinder or clean contacts. If you clean contacts, leave harnesses plugged in then take black plate off. If you don't, they will fly everywhere and they will be in your backseat. Take picture of contacts then unplug harnesses and get contacts out. If you take these contacts out and don't put back in correctly it will not crank. Good luck. Why isn't this on the recall list again?

My car has been doing this for years at random times. Mainly when in a hurry or running late car security light comes on and won't crank. Move key to acc for 10 min (I always go 12 because if you go 9:59 it wont crank and you will have to sit again lol). A GM mechanic online somewhere recommended a relearn process 3 10 minute cycles then crank. That didn't work. So I saw the resistor bypass online and got some resistors. I am no mechanic but know electrical principals and this can work. It is my understanding (from dealer) the key ignition is looking for a certain resistance (ohms) and it says there isn't a key in ignition so wont crank.

First I am no mechanic and I was not prepared to do this no mechanic wanted to do a bypass. I took dash apart and followed youtube vid 7mm screws got dash off broke two clips.. Oh well (you have to drop shifter down to pull out). Took radio out and looked to the left and it wasn't open like vid was. Finally I figured out I could take big metal plate off under steering wheel. Took that off with 10mm deep socket and long ext. 4 screws.

Any time I messed with ignition cylinder contacts I took battery connections off. Not sure if that's right but I didn't wanna burn anything up.

While I had apart I replaced dimmer switch (dash lights not working) and old one was burned up electrical contacts oxidized. So I though maybe ignition contacts are bad. So I unplug Transaxle cable(I think that's what its called) And two harnesses to get slack to get it closer to me. Then I take plate off back and I find out those harnesses are what hold the electrical contacts in the fly everywhere 4 pieces. I hunt them in the rain and they are solid white. I took inside with towel and baking soda and cleaned all of it came off. They are brass or mixed metal.

Now I have to put contacts it back together.... It took me a while to figure out because nothing online showing pictures. One piece slides in on right side with 3 bars and left with 2 I believe you can see points just below to know they aren't backwards. But there are pieces that hook on the top of each buss bar they have to be put on before inserting into ignition. Once you have them set in all the way absolutely perfect plug harnesses back in.

My car has been fine for months and was not cranking every two cycles before had this problem off and on for years. Once again I am no mechanic If you take ignition apart and don't put back together right it will not crank as mine didn't I got every light there was gauges didn't work. Finally I fixed but this was because mine flew everywhere when I did not know harnesses hold in place. Good luck.

Something told me to get the grandma looking Mercury Sable....... but my husband wanted the very nice looking and somewhat rare Impala LSX 3.8L V6. Here is the issue, started out fairly minor and on rare occasion it wouldn't start. Leave it set for about ten minutes, then vroom vroom. Then it was happening a few times a week, then every day, then multiple times a day. Now it sits with the hood up outside in the driveway refusing to play nice. At first the not starting would be accompanied by the security light, but not anymore. Let me say too, that as the issue became more frequent, when it would finally start, the dash lights would begin spazzing out a bit. I'd have the airbag guy come on, and the NO TRAC light, and the ABS light, and sometimes, you could just hear the electrical stuff buzzing in the dash. When it was spazzing really bad, even the turn signals wouldn't work and the transmission would hardly want to change gears(which I just had rebuilt around June----AAARRRGGGHHHHH). Drive around for a couple of minutes and everything would normalize. Was considering taking the car to the dealer to get repaired but after checking a multitude of forums and such, it looks like the dealer service departments have only fixed the issue a handful of times. I am considering getting a remote starter or something. I called GM to get some answers but they only wanted to tell me about the recall for the engine fire crap. I told him that I wasn't too worried about that. NO START means NO ENGINE FIRE........I will not likely ever get another Chevy. Side note, right before these issues started, I was having a bit of difficulty turning the key in the ignition. I would have to keep turning and holding my steering wheel in different positions to get it to start. I have a 1994 Ford F150 pickup truck that I consider to be my reliable vehicle....... go figure. Hey, anyone in the market for a somewhat rare, non starting Chevy Impala?

For all of you having intermittent start problems with the security light coming on, it's not the starter, it's not the battery but it is the ignition switch. The ignition has a chip in it that has gone bad and this is what is causing your intermittent start problem. A temporary fix is to turn the key on for 8-10 minutes ( when it fails to start) and leave it on and just wait. During this time the ignition has to relearn itself to your key. The security light wil be flashing as well as the battery light. Now after the 10 minutes or so, turn the KEY OFF then attempt to resrtart it again. I know this sounds like voodoo, but trust me it works and it'll get you going again. Sometimes it works in less that 10 minutes.

A new replacement ignition is upwards of $300 at a repalir shop or you can get a new switch at your parts store or ebay for under $100 and do it yourself by simply removing the dash bezel. Go on line for some detailed instructions . The ignition comes in two parts, the ignition and the tumbler that the key goes into. To keep your old key you'll have to change out the tumbler pins, just do it in the same order as the old tumbler.

My wife just keep a good book handy as she waits. I'm waiting for warmer weather and some spart time to do mine. By the way this problem is not just unique to the 2003 Impala, it's all GM products.

Here is our problem the car would not start, always at most inconvient time. We have to sit and wait for about 15 or 20 minutes until the system reset itself. Then with all the windows rolled up and every thing in the off position only then could we could start it. I tried several of the methods described in complaint notes the results were the same. After 6 years and several towings it started getting more frequent, once or twice a month. Finally it did not start at all. Our mechanic said we need a new iginition switch and key cylinder. This was replaced for $600. And all was great for 30days when the switch broke again and would not start. This was replaced under warrenty and the new one is doing great and some other small problems have went away. We wish we would have done this sooner.

My 03 impala has had issues with no current being sent to the starter motor at ignition. I had the car towed home and replaced a perfectly good OEM starter motor with a crappy Autozone one. This fixed the problem for about 1 week. At the same time I was shorting my automatic door lock fuse about every 5th vehicle entry. I have not resolved the problem but have mitigated it by using keyed entry instead of remote entry. This has worked without a failure for the past 3 years. Before I resorted to keyed entry, I could always get the starter motor to work by pulling and re-inserting the 10 amp PCM fuse on the driver side fuse panel. This worked on about 10 different occasions (never failed) before I stopped using remote entry and the starter motor problem went away. If you're in a bind and the starter motor won't get power, pull the PCM fuse and put it back in. I choose the keyed entry approach now because pulling the PCM fuse resets all of the transmission gear shift settings and takes a few drives to get back to normal.

I first had the Passlock problem over a year ago. I did the "turn key to ON and wait 10 mins til Security light stops flashing" thing a number of times. Then my key also started getting stuck in the ignition, so I had the tumbler replaced. No Passlock problems after that! Until one day last month, the dreaded Security light came on while driving and, soon enough, was dealing with the won't start issue again.

I looked anew for solutions and came across the following (maybe on this site, but I can't recall) and it has been working so far (three weeks). The light has come on a few times while driving, but using the following steps every time I start the car, I have not had the "won't start" problem. I do not know if this a real solution, or just coincidence that my car has started every time. But I'll continue to do it until it's proven not to work:

Every time you drive:

1. Get in the car and close the door. 2. Put the key in the ignition and turn one click to the right, to “ACC” Wait two or three seconds until the (faint) electronics noises stop 3. Turn the key to the “ON” position (do NOT turn all the way to “START”) 4. Wait 5+ seconds for the bells and other noises to stop 5. Turn the key to Start. 6. (Assuming the engine started), put on your seat belt and off you go...

Like I said, this is working for me so far. I hope it is a solution, not just a coincidence.

Update from Jul 18, 2012: I have continued to use this method and it is still "working."

So if you are one of those who occasionally has to do the whole "Wait 10 mins until the Security light stops blinking" routine, then I recommend trying this approach.

Tim, MN

Update from Aug 19, 2012: AUGUST 19, 2012 PDTE

SORRY TO SAY THATWHAT IPOSTED BELOW BAC IN MY IS WAS NOT A "SOLUTION' AFTER ALL BUT JUSTA COINCIDENCE. THE PASSLOCK PROBLEM IS BACK, AND WORSE THAN EVER. THE PAST FEW DAYS THE RESET HAS OCCURRED EVERY TIME I TRY TO START THE CAR, AND IS TAKING ONE, TWO, OR EVEN THREE 10-MIN CYCLES... YESTERDA, I SAT FOR 30+ MINS AT A GAS STATION....

I first had the Passlock problem over a year ago. I did the "turn key to ON and wait 10 mins til Security light stops flashing" thing a number of times. Then my key also started getting stuck in the ignition, so I had the tumbler replaced. No Passlock problems after that! Until one day last month, the dreaded Security light came on while driving and, soon enough, was dealing with the won't start issue again.

I looked anew for solutions and came across the following (maybe on this site, but I can't recall) and it has been working so far (three weeks). The light has come on a few times while driving, but using the following steps every time I start the car, I have not had the "won't start" problem. I do not know if this a real solution, or just coincidence that my car has started every time. But I'll continue to do it until it's proven not to work:

Every time you drive:

1. Get in the car and close the door. 2. Put the key in the ignition and turn one click to the right, to “ACC” Wait two or three seconds until the (faint) electronics noises stop 3. Turn the key to the “ON” position (do NOT turn all the way to “START”) 4. Wait 5+ seconds for the bells and other noises to stop 5. Turn the key to Start. 6. (Assuming the engine started), put on your seat belt and off you go...

Like I said, this is working for me so far. I hope it is a solution, not just a coincidence.

Update from Jul 18, 2012 I have continued to use this method and it is still "working."

So if you are one of those who occasionally has to do the whole "Wait 10 mins until the Security light stops blinking" routine, then I recommend trying this approach.

Tim, MN

Car's security is starting to fail. Came on here, saw everyone else having the same problem and decided to throw in my two cents, since it's a pretty simple fix, that doesn't cost anything at all.

Not sure how long this fix will last though, considering this just started happening to me a month ago.

I came back from Vegas after 4 days, and my battery had drained and died (faulty alternator, most likely). Got a new battery, everything was fine for 6 days. Then, one night leaving work, didn't start again. Car didn't clank, engine didn't turn. Knew it wasn't the battery. Left it alone for a while and came back to it, started right up. No big deal.

Did it a second night in a row. Started a little sooner this time, but starting to get annoyed by it.

Just happened again today, for the 3rd time in a month. My dad tried a few things, since it used to be his car before I got my license, and he remembered a trick (I guess the car had done it to him before): turn the key to the on position, turn the radio and air off, and hold down the tune button. After about 7-8 seconds, the radio starts going berserk and resetting the security on the car. Once the radio stops cycling through the options on the car, just start it up, and it should turn on right away. Hope this helps anybody else out there.

So much for a joyful Thanksgiving Day. As I went to start the car, it wouldn't even click like it was a dead battery. After attempting to jump the car, at first it wouldn't respond but eventually started after about 10 minutes. I went to the auto parts store expecting to get a new battery but after checking, the battery and alternator were both good. No further problems but now I'm nervous everytime I start the car. After reading all the complaints, at least I know I'm not alone. I don't expect a recall because nobody has been killed yet. Companies don't care if we are only inconvenienced.

I have replaced factory starter with rebuild starter from company called Hite .We use their starter and alternator in our fleet of Ford F-350. We've always get good rebuilds from this company for many years. Any problems with their rebuild they always make it right. I was having the the start trouble two months ago,HITE replaced start with a rebuild. I replaced starter car started ,no problem until now. I have a jack and two jack stands in my truck ,so I can get under car to tap start . That doesn't work. I've checked all the wires that are on starter,they're tight. Cleaned cables to battery,very clean. List to this I had to move my car up three feet,so mail could be delivered. I thought what the ...... I try to start and it STARTED... SO WHAT IS NEXT?

the car just wont start from time to time, and in the last 2 weeks it has happened 3 times. and from what i can see it is a flaw in the vehicle. so why is this not on recall list. the car runs excellent except for that problem and it is making me want to scrap this car and go to a different make and model. i have put so much money into repairs in the last 5 yrs owning this and now because of flaw on the manufactures i have to still put more money in it.. that really sucks... there should be a recall and let the consumer get it fixed for free....

I have been dealing with this problem since before the car was out of warranty (<36,000 miles). At first it was only occassionally. It was seen by the dealer I bought it from four times when I first had the problem. They replaced the starter once. Then the Body Control Module. Now it seems to happen more frequently. I just found this site. I am exasperated that GM has not recalled the car.

I have purchased GM cars since 1976. My father-in-law is a GM retiree. We have been loyal to this company for all this tiime. The fact that there is nothing being done means they just don't care about the customer. It has been a great car, except for this problem. The Bose sound system is the best I have ever heard.

Everyone has talked about the Passlock problem on the Impala. I have been going through this since my 3 year warranty was up. It gets worse throughout the years. I first had the dealer change my ignition out for over $600 and it did not fix the problem. I then found this site. Even if they fix it, the problem most likely will come back. There are two other things people talk about on fixing it but none of it will last. Started off not starting once every couple months to once a month to once every two weeks to every day and now to more than once a day.

Will never buy GM again because they know about this problem and play dumb at the dealerships. This problems has been going on for years. It also happens to the Malibu and other Chevrolet vehicles that have the same passlock.