Shuts off suddenly while driving

Hi,

The idea that it reacts differently at different times leads me to believe it is something with a module or a bad connection.

Here is what I suggest starting with. Have the CAN-bus system scanned. CAN stands for controller area network. The vehicle has several modules/computers in it. They are all tied together via a few wires to help eliminate the need for giant wiring harnesses and weight. If you use a basic scan tool, they usually can't identify anything other than a powertrain code. However, there are other modules that may be storing diagnostic codes. By scanning the CAN, it will identify anything that is stored regardless of the module it's stored in.

Here is a quick video showing how it is done:

https://youtu.be/InIlnsjOVFA

I suspect it could be something related to the ignition switch since it isn't recognizing 2 different keys when this happens. Do me a favor. I want you to remove fuse 78 (pics 1and 2 below) and check to make sure it's tight and there is no corrosion. This fuse should be in the body control module under the dash (I believe the passenger side).

Also, carefully check the mega fuse 4 in the battery junction box (BJB).

Both of these fuses have to be good because the problem comes and goes. However, I want them checked because you mentioned sometimes you lose dash lights. Something could be causing a loss of connection such as corrosion, being loose, or partially blown.

If everything checks good, have the CAN scanned to see if there is anything stored. We may end up having to have the BCM reprogrammed. Also, make sure the battery terminals are clean and tight, free of corrosion.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Let me know what you find.

Joe

See pics below.

Hi,

I'm sorry, but the person never replied. Is your vehicle the same year, make, and model as above?

Let me know.

Joe

Hi,

It could be anything. Does it only stall when the engine is warm? Also, the CAN scan is our best chance of narrowing things down. As far as the oxygen sensors are concerned, they won't turn the engine off like this.

Are you able to have the scan done?

Joe

Hi,

Certainly, it could be a faulty fuel pump, but they usually don't act like this. To confirm it is a fuel pressure issue, pressure needs to be tested when it won't start. Heck, see if it starts for a couple of seconds using starting fluid. If it does, then it is fuel related.

As far as the symptom, it could even be a failing crankshaft position sensor. Take a look through this link and let me know if it mirrors what you experience:

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

Let me know. Also, let me know if you are getting the starting system fault or no key detected indicators. Because they are turning on, I don't feel the pump is the issue or even the crankshaft position sensor. I feel it is related to the immobilizer, but we really need the can-bus scanned. Otherwise, it becomes a guessing game. I hope you understand.

Take care,

Joe