I came across this article Mythbusting: The “Carrington Event” and Solar Cycle Doom That article is full of innuendos, misdirection, half-truths and downright untruths.

First off a CME is not the same as at EMP.
Any author that interchanges the two had absolutely no credibility.

The main difference between an EMP attack and a CME impact is what is effected.

For EMP, both the power grid and electronics are damaged and destroyed.
In a CME impact, mainly the power grid is affected, while electronics are untouched

The three components of nuclear EMP, as defined by the IEC, they are called E1, E2 and E3:

• E1– The first component is a very fast, high voltage pulse. It is very brief, but very intense.
  It is much faster than lightning and common lightning and surge suppressors will not stop this pulse.
  It induces high voltages in wiring and cables, like power lines, phone lines, etc.
  This is the component that destroys computers and electronic equipment.
• E2 pulse is a lot like lightning and is easier to protect against, though if the protection circuit was destroyed or damaged by the E1 pulse, may still do more damage.
• The E3 pulse is a long duration pulse and is no like the E1 and E2 pulses.
  It’s a very slow pulse, which can last up for minutes.
  It is caused by the nuclear detonation disrupting the Earth’s magnetic field. Which sounds a lot like what happens during a CME impact. This is the wave that shuts down the power grid. It does this by inducing a DC-like current. When enough DC current flows through a transformer, it melts.

While a CME can damage electronics in space, such as those on satellites and on the Space Station, it doesn’t generate any E1 pulse.
A severe CME could take out large portions of the power grid out for years, but they would not damage any electronics equipment down here on Earth unless, perhaps, connected to the power grid or other very long lines

Next.
In the book “One Second After” the story is based around EMP, not a CME.
“A war based upon a weapon, an Electro-Magnetic Pulse (EMP)”

The 37 car test.

I’ve seen that referred to a bazillion times but nobody ever talks about (in my best Paul Harvey voice) EMP Effects on Vehicles page 2. (please read it)

 The U.S. EMP Commission tested a number of cars and trucks at the L-3 facility in Colorado.
Although this was the most comprehensive set of tests on vehicles that has been done, those tests were very poorly done because the Commission was financially responsible for the vehicles,
but did not have the funding to pay for any of the vehicles they tested.
The vehicles were borrowed from other government agencies (most vehicles came from the Department of Defense); and the vehicles had to be returned to those lending agencies in good condition.

Those vehicles were tested up to the level that some sort of upset occurred, then further testing was stopped on that vehicle.  In most cases, after the initial upset occurred, the vehicle could be restarted. In most of the remaining cases where the vehicle could not be immediately restarted,  a latch-up had occurred in the electronics, and the battery could be momentarily disconnected to “re-boot” the electronics, and the vehicle could then be restarted.
This temporary electronic latch-up failure mode caused by EMP is something that almost never occurs in automobiles during a typical lifetime of operation.

Very few of the vehicles were tested up to the maximum level of the EMP simulator.
There was considerable disagreement among Commission staff members about how to report on the testing that had been done.

Some EMP Commission staff members believe that the wording of the paragraphs in the EMP Commission’s Critical National Infrastructures Report about the effect of EMP on vehicles is quite misleading.

Check out the List of solar storms complete list of CME’s  that have hit Earth.

I encourage everybody to do their own research and not take things at face value, including what I just wrote.

Just my two cents worth