2006 Chevy Impala won't start

[Jeremy]

My 06, impala 3.5 just died going down the road the key does nothing the dash lights don't come on can't roll up the window. And the scan tool I plug into the UBD2 linking error. Under the hood I found a blown ECM 10 amp fuse replaced it and still nothing. I'm thinking maybe my ECM needs replaced but of course I want to confirm before I spend the money with someone smarter than me. Thanks for what ever help you can give

[carriedi]

doubling up on the posts? ecm/tcm 15 amp fuse powers up the engine and trans control modules. They make tools that you put in place of the blown fuse and can check the amp draw. you could measure the amps that are flowing through that circuit.

If the fuse doesn't blow, after replacing the fuse, check the powers and grounds for the ecm and tcm modules to see if they are both powering up or not

[Blueprint526]

I’m new to this and I can’t make a new topic.

I have. A 2010 impala l. 3.5 ls. What I have going on is when I first start the car I have no symptoms. The car drives perfect. About 10 to 15mins in when I approach a stop of any kind. I notice my speed o meter some what irractic. It goes up and down on its own and will shut off then and there with in 5 second tops. I also pu my digital speedometer display and it will say 112 mph( while I’m at a complete stop on drive). The trick I have working for me is coming to a stop I put the car on neutral, in which the car won’t shut off but still do the up and down on the speedometer needle. I have put a fuel cleaner no change.all my oils are at the correct levels. I also have NO CHECK ENGINE LIGHTS ON. Please if I can get advice on where to begin I would appreciate it. I’m a DIY SO I’m looking to solve this one. Not sure if it’s conecred but I also only have a/c blowing. I put the controls on hot by no hot air comes out at all not even while driving.

[carriedi]

you should use a scanner and see what the computer sees as speed. If the speedo and the computer don't match and the computer shows the correct speed then you may have a bad instrument cluster. The speedometer get it's information from the PCM. Scanning the pcm you should get the speed PID that is being sent to the dash. There may not be an engine code so no check engine light but scan for BCM or IPC codes

[Blueprint526]

I will try the odb reader. But I don’t think the speedometer being messed up would result in my car constantly shutting off at a stop. The car feels like it is choking before it shuts off. I have to rapidly place it on neutral so it won’t shut off.

[carriedi]

ok, so it's not that your speedometer shuts off, your engine shuts off at a stop. Or your engine stalls at stops.

a code reader and a scanner are not the same thing. A scanner will let you see the data stream. this way you can see what your computer is reacting to. what your fuel trims are. what your idle control is doing.See if your torque converter is releasing.

you said you notice it beginning to happen and you put the car in neutral to keep the engine running, what if you raise the engine rpm and use the brake? basically, power brake the engine at the stop? will it still die or can you keep it running?

Here's the thing, if the speedo goes erratic when coming to a stop and the engine stalls when coming to a stop, maybe it's connected. Maybe not, but you're going to have to try and figure out is it is related or if it's just a coincidence that they both happen at the same time.

[Karry]

Chipped key for the car will not start the car anti-theft indicator off check engine light airbag lights on not flashing when attempted to start you get one click there's power to the radio windows and headlights the power to the battery reads like 13 right now we unplug the battery doing the 30-minute wait and seeing if it resets the CPU to see if the car will start story is I locked my vehicle went into 7-Eleven I came out use the key to unlock my door guardian we just started one click cars doing nothing else I look over to the right my passenger door is unlocked I believe somebody attempted to steal my vehicle and the anti-theft was engaged and yet there's no indicator on the dashboard there's nothing wrong with the key I've had this car for a year I also I forgot I also tried to jump start it and that didn't work either

[carriedi]

"attempted to start you get one click" what does one "click" mean? Are you saying that the starter solenoid give one click? (could be that the solenoid is pulled down but the starter contacts do not make a good connection.

If it's possible, you should run a wire to your starter solenoid, to a test light and see what the signal to your starter is doing. It's possible that the starter is the problem. Depending on accessibility, tapping on the starter while trying to start the car could make the starter release and start up. (that would be after you verify that the starter solenoid is getting the correct signal from the ignition switch)

when you put your ignition switch in the start position it sends a signal to the body control module (BCM). The BCM sends a signal to the engine control module (ECM). the ECM sends a signal to the starter relay in the underhood relay box by the right strut tower. And the relay sends the signal to the starter solenoid on the purple wire from the relay.

So, you have quite a few things that control the signal to the starter solenoid. If, while you have a test light hooked to the purple starter wire or at the starter solenoid terminal, see what the light tells you about the power to the solenoid. Does it turn on at all when you put the key in the start position? (if not you have to trace the starter circuits to see where you lost the starter circuit) Does it show power to the solenoid and then shut off right away? (then you have to check the BCM, ECM for security issues) Does it show power to the solenoid but after the click of the solenoid nothing else happens? Then you need to look at the starter for problems.

Without hearing the type of click you are talking about it is hard to know where exactly to look. But if everything else is looking normal and the security light is not on, I would suspect the starter first. I have a tool that replaces the starter relay and it lets me bypass everything and put power right to the solenoid to check the starter side of the circuit. Quick and easy, pull the relay push the switch and see if the starter cranks over or not. Once that part tells me what happens I go from there. If the starter cranks until I turn the relay off then the starter side is good. If then the key works normally then it could be a bad spot on the starter and will probably happen again later on. If the starter does not work with the key after the relay bypass showed that the starter did work I would use a scanner and look at the security system to see if there is a problem and go from there.

I know this is a log drawn out post but there are many things that could be the problem here. I hope I didn't make thing too complicated but I would check the basics first. The signal at the starter. That would give you the best clue on what is happening and where to go from there.

Let me know what you find out and I can go on from there.