2002 Chevy Impala electrical problems

Full day test drive, there were no problems at all.

After buying, noticed many weird electrical things: - Blinkers are spastic - Dash lights very low, can’t turn up. - Turning knob for dash lights causes radio display to flicker and turn off - Security alert on dash stays on sometimes

Shortly after buying car in September, A/C stopped working. Brought car to Brian (mechanic/friend), who found A/C fuse blown, replaced it, then it blew again right away in his parking lot. He noticed it popped when the cooling/radiator fan clicked on. He put in a bigger fuse – and told me to never do that on my own.

October/Halloween – I was driving down gravel road, tried to turn on headlight BRIGHTS, pulling and/or pushing blinker stick didn’t work. One attempt to pull on blinker stick turned on brights, but upon letting go of the blinker stick ALL lights went out. I pulled over, decided to turn car off/on to see if headlights would work. Turned car off, it wouldn’t re-start, turned the key with no response at all. Pulled car out of park, back into park, and the car started. Not sure if that made a difference.

At Christmas time, car wouldn’t start in Lewis parking lot. Checked fuses, A/C fuse burnt out. Husband pressed on other fuses, car started. Took to Brian, he said starter relay loose, tightened and it’s fine. A/C needs coil replaced, he has one in scrap car will replace at later date since now winter and don’t need A/C.

Couple times recently, turn key but won’t start, try again and started fine. Asked son if any trouble starting car, he said no.

2/4 (last night, 10 degrees 9pm) Son called from high school parking lot, car won’t start, makes no noise, other boys tried to help by jumping but wouldn’t start. Battery not dead radio and lights are fine. When I got there I tried pushing on fuses like had done, but car wouldn’t start. Closed door, locked, and walked away to go home, could see and hear radio still on – weird. Radio staying on when car is off and locked. Manually turned off radio, but display and dash lights are still on after door closed and car locked. Went home and had to leave it like that.

HOURS of research today, read almost ALL complaints here on this site. Also found LOTS of YouTube videos. One said to use radio to control some settings including turning off security alarm. I will try that when I get back to the car. Another video said to check interior fuses including the cluster/BCM fuse, take it out and put back in over and over until the car starts. Another video showed the guy finding the ground wires for the starter and he could wiggle and press those while someone started the car. That would explain a lot of the complaints here that say the car stopped running while driving (so frightening!!!). I will also look at that when I get back to the car. Lots of comments on the youtube video about using the radio to turn off the alarm, said it saved them being stranded.

It seems the consensus of my research today is that the security gets whack, and the ignition switch gets bad (dirty contacts?) sending bad signal to the BCM or passlock, and the car thinks it has to stop thief. So it engages a 10 min lockout starter kill delay. That would also explain why many comments here mention the car starting after waiting 10-30min. Mine didn't... So, what is causing the glitch in the security to engage that lockout delay??? BCM? Passlock sensor? Ignition switch? Whatever the issue is, is it also affecting my headlights, dashlights, radio being on after the car is off, and the blinker being spastic????? I'll let you know if this ever gets resolved...

All I have to say is "Thank you, Chevy, for locking me out of my own damn vehicle that I, THAT I, bought from you. You succeeded in locking me out of my car more times than any thief has attempted. Oh, yes, you were the thief in robbing me of my hard earned money due to confusing certified repairs. I can't blame the hard working mechanics that had a hell of a time trying to fix the problem. No wonder it's their policy not take returns on electronic crap because it is crap. Been debating on what car I should get next. The only reason I would buy another Chevy is because of the actual caring servicemen at Commerce Chevrolet. It took lots of effort for me to gain their trust. They actually carry the name appropriately (not the manufacturers.) Not only did they lose lots of time and money, so did I. I should have kept my Ford after all.

Update from Jun 21, 2022: It will leave you standand and when you take it to the shop, they will say "I don't see anything wrong with it." Which is true at that moment. Drive away and it will not recognize your key again for about 15 minutes. Very frustrating so go with a Nissan!!

In 2011, I inherited a 2002 Impala LS V6 3.8L with nearly 200K on the odometer. Fuel gauge no longer functioned, but otherwise a real trooper. Impressed that it just keeps going, with minimal upkeep.

Passlock problem: Didn't occur for the first 9 years, but appeared at 200K, in 2012. I suffered for about 18 months of not knowing if the car would start at any given time. Initially I had to wait from 10- to 40 minutes for the car to start. I later discovered that after ten minutes, holding the key in the start position for a lengthy 4-5 sec would start the car. Typically we are not habituated to holding the key in that position for more than a second or two.

Remarkably, after 18 months, the problem no longer occurred. It just "went away." The Security light still appears at random times, but is harmless otherwise. Been driving 18 months since, without any problem.

I wasn't going to invest big money into an uncertain repair- so i adapted to the problem (commuting early). Strange that it resolved itself, and the main reason I'm reporting it here.

Check engine light would come on then off at times. Then Security Light came on and would not go off. Garage checked into it and told us to use our other key. Security Light would come on again and stay on for long time then just go off. Time went by car would not start suddenly, would not jump, would not turn over. After waiting between 20 and 45 minutes it just started like nothing ever happened. Happened a few times, towed to garage. Computer said it was ignition. Put in new ignition but not Chevy part. Worked a couple days, more problems not starting. Same garage said there was something wrong with new part and put another new ignition in. Okay a short time and problem started again. This time we put in a chevy ignition and worked for a while. This is crazy. Not dependable. Will start every day then suddenly NOT. Sometimes when it does not start the security light is the only thing that lights up when turning the key, no sound. Other times radio and lights come on but again no turn over sound. Wait the 20-45 minutes it usually starts like there is no problem.

There must be an answer

I am aggravated, frustrated and mad at GM for not acknowledging this problem long before now and not taking any action to address it. This has previously caused me to be late to work. Has happened when I have had grandchildren with me. I have had to sit in front of the gas pump blocking other autos when it would not start after I stopped to get gas. This has happened in the winter and I have had to sit in below freezing weather waiting for it to straighten up. It generally takes longer than 10 minutes.

My father worked for GM for many years and would only purchase Chevrolet's. He always told me that that was the only car worth buying. Well, I finally bought one and guess what - problems that the company from which my father retired will not address it. Sorry, dad, but the company is NOT all that you thought it was. Maybe it was better back in the day, but no more.

We also have a 2002 Impala with innumerable electrical issues, one of which was the Passlock system shutting down the fuel pump. We didn't want to start throwing $$ at the car, not knowing which solution would be the one to work. This issue didn't happen on a regular basis, so for a few months, when the 'reset' plan that had once worked stopped working, we resorted to disconnecting one of the wires to the battery and then reconnecting it. That was a great plan until I broke one of the nodules off of the battery!

Within a blog, we ended up finding a resource for an electrical harness that bypassed the security system. It was the best $250 ever spent on that vehicle. Though the security light still comes on to haunt me from time to time, it starts up like a charm every single time! Now if I could just figure out the other electrical issues....

I am absolutely amazed at the number of cars with passlock/security issues. It is a safety hazard to be unable to start your car in an emergency or left stranded with even children. Does anyone have any information about a class action lawsuit...this site poses undeniable proof of a design flaw in so many of these cars and we should not be burdened with the cost. I am having my car towed to nearby mechanic who is familiar with these issues so I'm not not forced to buy a new computer off the bat. He said it's extremely common and happened to his own Pontiac. No wonder GM need a F*$king bailout! I also had to replace the flawed plastic intake manifolds...sound familiar? Where's our justice?

I HAVE A WORK AROUND FOR THE PASSKEY/PASSLOCK II or III sensor problem on the vehicles equipped with such. It takes less than 1 minute. PROBLEM: You try to start your car as normal and BAM! SECURITY ALERT- I AINT MOVIN. The security system locks you out of the ignition system and the SECURITY light flashes 3 times. You have 3 choices at this point. 1st yell and scream and literally beat the crap out of yourself until you are a pulp of pissed-off mess. 2nd you can wait 10-11 minutes with the key out of the ignition (ACTUAL minutes, not estimated) then try again hoping it will turn over, to no avail, it happens again forcing a loss of another 10 minutes possibly another 20, of which is very valuable to me. By this time it should start. After re-learning the key's resistor level it better start. Stupid RESISTOR KEYS AND ASSOCIATED SYSTEMS! Best anti-theft device is a colt 45 with laser-aim. 3rd option is take it to the dealer, get told we don't know what the problem is and then be told we have to replace the bcm, ecm, ecu, pcu, pcm, or some other alphabetical based black box somewhere in this hunk of junk, that cost about 50 bucks and 500 in labor cost. You can settle with that or even buy a bypass module that MAY NOT EVEN WORK. With that said, I have a new solution that has taken me from the security light lockout 2-3 times a day to the past 6 months with no occurrance. I had 6 of my friends that had the same problems with their passkey/passlock II and III systems - bending them over and nailing their exhaust pipes before becoming sweet and starting after the reaming- try the same thing I did and it worked for them as well. Out of the 6 only 1 reported having the security system locking them out twice during the past 6 months.

HERE IS WHAT I DID AND HAD MY FRIENDS DO:

If your car has been sitting while you were at work or home or in the store, and you are coming out to leave, follow steps 1-6.

If you just had the SECURITY SYSTEM lock you out of the ignition system, you will have to wait the 10 minutes for it to reset and allow the ignition control module to interact with the system. Once the 10 minutes have passed from the ACTIVE SECURITY STATUS, follow steps 1-6. Do not try to shortcut this as it wont work.

If it is raining, you can close your door, just not all the way. Close it all the way and open the door latch without pushing the door open. This will keep you dry.

+++++STEPS+++++ 1.) OPEN YOUR DRIVERS DOOR AND SIT DOWN. 2.) PLACE KEY IN IGNITION, WAIT FOR CHIME. (3 seconds is what I usually wait) 3.) TURN IGNITION 1 CLICK RIGHT (TO THE ACC POSITION) AND STOP! Do not continue to ON and START yet. WAIT ATLEAST 5 SECONDS 4.) AFTER 5 seconds has passed, TURN KEY TO ON and STOP, DO NOT CONTINUE TO START YET! 5.) WAIT AND WATCH. With your drivers door open, here is what you will see and hear = Your notification will signal DOOR ADJAR, then the BATTERY light, then the SECURITY light, during which you will hear the chime sound as if you just started the car. 6.) AFTER YOU SEE THE SECURITY light switch back to DOOR ADJAR or Battery, and after the CHIME has stopped, you can turn the key to start and voilå!

It has worked every time for me and 5 of my friends. This whole process takes about 20-30 seconds, but it sure as hell beats 30 minutes, as GM refuses to compensate my time lost to their vehicle's design flaws.

RECAP: 1.) Open driver door, sit down 2.) Insert key in ignition, wait for chime 3.) Once chime starts wait 3 seconds 4.) Turn key to ACC position WAIT atleast 5 seconds 5.) After 5 seconds turn key to the ON postion and wait for the security light to switch back to Battery or DOOR adjar, and the chime to stop (Do not try to START if the chime is still sounding) 6.) Once chime stops and Security light has passed, You may now complete the turn to START and it will start.

Note: This is not a permanent workaround, but it will buy you some time, I can almost guarantee it will work for most if not all people, almost all the time.

If you follow these steps and it works, email me at kevintampa5@yahoo.com to let me know your results. If this did not work for you, it may be an actual failure of the system and not just an argument between the key and the car, in which case I wish you the best of luck and hope you get it fixed. I dealt with this problem for 2 years before I tried this method. Worked wonders for me. I am actually on time for work every day now. No thanks to GM, sorry to say. Disappointed in their new products.

IF the security display flashes on the information panel with the door closed the problem is with GM's worthless Passkey2 system. Here's how to fix it: The problem is NOT the tumbler or the starter or ignition switch. It is the blind plug behind the ignition key tumbler that connects the hall effect sensor in the tumbler to the Passlock2 system. The pin connector gets slightly corroded, causing a different resistance reading, locking out the security system.

Buy some small heat shrink tubing and a car repair manual (about $22.00 at an auto parts store), a small soldering iron and fine resin core solder (about $18.00 from your local electronics store). Disconnect the battery. Tear apart the dash center cover, unbolt the ignition switch but DON'T remove it, just cock it to the side so you can remove the tumbler (Read the manual to figure out how, it's not very hard). I also removed the ash tray assembly, but that may not be necessary. Remove the three pin plug from the switch assembly. Figure out and write down which wires go to which pin, cut off the connector, feed the wires through the hole in the switch where the plug was and each wire through a 1" length of heat shrink tubing, slide the tubing back up the wire aways and solder the wires to the respective pins. Slide the tubing down over the newly soldered wires and pins and use a hair dryer to shrink them on (so you don't get a short). Re-assemble the ignition tumbler and dash, reconnect the battery, put the key in the ignition, turn it to "on" (don't start it) and leave for 30 minutes so the computer can recognize the tumbler again. Voila! Problem solved, guaranteed. Worked beautifully on my 02 Impala with this exact problem. It would turn over, but never start, as the Passkey2 system disables the fuel injectors. The (tin plated) connector and pins will oxidize over a period of time (varies depending on how humid an area you live in) and cause a false reading. I figured this out after days and days of research online. Apparently Monte Carlo's of the same vintage have the same problem.

I sure hope this helps a few folks. Whatever you do, don't let the dealer fix this, they will replace the ignition tumbler and/or Body Computer for hundreds of dollars, and still won't fix the problem, because the problem is the stupid little three pin blind connector the tumbler plugs in to. GM should have gold plated the plug connectors and the pins due to the very low signal the hall effect sensor in the ignition tumbler produces. If they had, this would never have been a problem.

I bought my 2002 Impala back in April 2011. In July I had my first no crank situation. I had no tools at all on hand so I thought the starter was going as the starter relay was making noise and I did swap it with a cooling fan relay with no fix. After 10 min of screwing around it magically started. I was thinking about getting the starter rebuilt but didn't get around to it. A week ago it did it again. I jumped the starter and the starter worked fine but no start. Try the key and still no crank. That's when I searched the problem.

I took the ignition out and cut the yellow wire to the passlock sensor. It would not crank, owners manual says it only cuts fuel.I hooked it back up and started it and then disconnected the yellow wire. It started fine but security light stayed on. I put my multi meter between the yellow and black wires while it was running and read 6.3k resistance. I had to buy a pack of 150 resistors to get the one I wanted. I soldered in a 5.7k resistor between the yellow to the bcm and the black wire. You cut the yellow and bare a spot in the black and leave it hooked up. The yellow to the key is no longer used. It started first try.

I used a resistor to mimic the passlock sensor in case the sensor fails.

This is the final solution to fix the Passlock II problem. As someone else already found out, the cheap tin contact of the passlock sensor are causing all the problems not starting the car and having the security light on.

Fix: Solder some new similar wires (yellow, white and black) directly to the little tin contacts of the passlock sensor that is embedded in the ignition switch lock cylinder.

How to get there: - Remove all the panels necessary to remove the ignition switch unit from the dashboard - find the 3 wires to the passlock sensor (white, black and yellow) and cut them anywhere. - once you have the ignition switch in the hand,remove all attached cables and clips, etc. - with the unit in your hand and the key inside and turned to ON, push a screwdriver in a small rectangle notch while pulling on the key and lock cylinder, to get the lock cylinder out (bit tricky, but do-able) - once lock cylinder is out, only now you can detach the passlock sensor connector with the three wires (yellow, black and white) from the ignition switch housing. - compare the passlock sensor tin contact with the matching connector to find out which wire has to be soldered to which contact. - go to a soldering professional to have some similar colored wires soldered directly to the tin contacts of the passlock sensor. I found one at a computer store and he charged me 8$ for the 10 min work. Make sure he fills the space between the soldered parts with silicon. - finally put everything back together and connect the new wires with the previous cut wires - now try to start the car, it probably wont, because the key has to be relearned:

1. Turn ON the igniton, with the engine OFF. 2. Attempt to start the engine, then release the key to ON (vehicle will not start). 3. Observe the SECURITY telltale, it will be flashing. After approximately 10 minutes the telltale will turn OFF. 4. Turn OFF the ignition, and wait 5 seconds. 5. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes. The vehicle is now ready to relearn the PASSlock Sensor Data Code and/or passwords, on the next ignition switch transition from OFF to CRANK.

IMPORTANT: The vehicle learns the PASSlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You MUST turn the ignition OFF before attempting to start the vehicle.

6. Start the engine. The vehicle has now learned the PASSlock Sensor Data Code and/or password.

I know this is more for the advanced mechanics, but it is the cheapest and only solution to fix the passlock problem forever. It worked for mine and I am driving for over three month now and never have to fear the terrible security light anymore!

Best wishes and greetings from Quebec!