No start, no crank, no click. Engine ground failure.

[abscate]

Two ways to check. Visual isn't too useful

Ir temp gun to see if the cable is heating with headlights on.

Check potential at both ends of cable with headlights on, should be equal within error of voltmeter

[markthomas1967]

That could be a remote starter or alarm System of course.

I am afraid I cannot start my 2004 V70 because my bad alarm system is telling CEM to immobilize. (Assuming it isn't the entire CEM going haywire, as I'm only now learning CEMs of this model and year are famous for?)
I seem to be having this problem chronically since arriving in San Diego. Cold and damp here (very heavy nighttime condensation). Was driving for weeks before this in TX, NM, AZ, no issues. First time this problem occurred was after a heavy rain in NY.
Today I did the alarm test where you lock the car with fob, reach in open window, open door with handle; no alarm sounded (I can, however, get alarm to sound using panic button on fob). Have never run this test before today, but the car has never "beeped" when locking car with fob.
Tried to test starter today by having someone crank while I took readings at terminals. Voltage normal between engine ground strap and positive terminal, but 0V from (white?) remote starter wire? Is this possible? Shouldn't there have been some reading?
How can I further test here?

[wizechatmgr]

That could be a remote starter or alarm System of course.

I am afraid I cannot start my 2004 V70 because my bad alarm system is telling CEM to immobilize. (Assuming it isn't the entire CEM going haywire, as I'm only now learning CEMs of this model and year are famous for?)
I seem to be having this problem chronically since arriving in San Diego. Cold and damp here (very heavy nighttime condensation). Was driving for weeks before this in TX, NM, AZ, no issues. First time this problem occurred was after a heavy rain in NY.
Today I did the alarm test where you lock the car with fob, reach in open window, open door with handle; no alarm sounded (I can, however, get alarm to sound using panic button on fob). Have never run this test before today, but the car has never "beeped" when locking car with fob.
Tried to test starter today by having someone crank while I took readings at terminals. Voltage normal between engine ground strap and positive terminal, but 0V from (white?) remote starter wire? Is this possible? Shouldn't there have been some reading?
How can I further test here?

You're likely going to have better luck in the P2 area of this forum where they often deal with the newer Volvos. These are the ancient dinosaurs that just refuse to die. =)