Little update
The Autel was able to correctly cycle the heaters and clear the codes for them.
But later on a P2459 code popped up. That is interesting because the DPF monitor is what I saw the first time I scanned it. So now it's saying it's not regenerating as expected. When I last scanned it two weeks ago it said it completed one 377 miles ago. He's probably put another 250 miles on it which is still less then the 700 I'd think it would take to trigger a regen.
The soot grams was at 37 when checked with the Autel. So I guess if the additional 250 miles added enough to reach the other threshold of 42 grams.
As mentioned earlier, the pressure differential was showing 0 psi at idle and about 1/2 psi reving it up a bit.
What are the chances the sensor from my 08 working on the LML? They look identical but have different part numbers. If they can interchange then maybe we can use it to see if it fixes his issues before spending money on unknowns
Should I run a service regeneration? Seems like it should be doing it on its own and a service regen is only a bandaid if the original reason isn't found. The code will likely just return. At least he will have another two years to work on it until the next smog check time