non start cranks will not fire?

Can I ask if the security light is flashing? If so, this is the problem, I would start by turning the system on and checking all fuses.

This guide can help:

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

If all fuses are good, please go over this video to help with the easy stuff:

https://www.youtube.com/watch?v=lXLJbuAZ4CE&t

C0899 - Device Voltage Low
U0020 - Low Speed CAN Communication Bus Performance
U0151 - Lost Communication with Restraints Control Module (RCM)
B1325 - Control Module Power Circuit Low

Confirm battery voltage is 12.4-12.6V with engine off. I have seen the instrument cluster go out can cause this problem but let's start with the easy checked first, please go over this post and get back to me.

Thank you for helping me.
So, there is no security light on dashboard, but the EML light is on.
Have checked fuses, all okay.
Tried everything in the video, no success.
Battery holding at 12.4v.
Really at a loss with this one.

With the key on, not cranking the engine over there is no security light on steady? Let's check for power coming out of the ignition switch when on.

Here is a guide to help with the ignition switch wiring diagrams below:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Check out the images (below). Let us know how it goes.

The light comes on then goes out within a few seconds.

Okay, that is normal. Please check the power above again, I updated it. It seems like the modules are not getting power.

12.16v at the ignition switch.

Disconnect the battery, then I would try unplugging the BCM electrical connectors and check for corrosion. Then plug them back in and clear the codes, this can reset the system, Also, I would do a hard system reboot.

This guide will show you how:

https://www.2carpros.com/articles/step-by-step-guide-performing-a-hard-system-reboot-for-your-vehicles-electronics-systems

Here is the location of the BCM, also does this car have interior water damage? Check out the images (below). Let us know how it goes.

Checked BCM wires all look fine, battery fully charged, and master reset as in your helpful guide but still won't start, starting to lose hope on this one.

How does the engine sound when cranking? Can you upload a video so I can tell if the engine is any good or not? Or you can do a compression test. Also, did using starting fluid change anything? does the engine have spark?

https://www.2carpros.com/articles/how-to-test-engine-compression

Please upload videos in your response.

The engine sounds normal when cranking, the starting fluid didn't make much difference, it tried to start but just would not go. It's a 2.2 diesel so has no spark.

Okay, I didn't know the made this car was diesel, sorry. I would send the BCM for testing.

I'm sorry but the advice you have given me doesn't sound like someone with 30 years of experience.

No problem. I will see if one of our other experts can help you.