Check your connections as stated. But your amp meter spikes don't sound too good.
Your voltage should be regulated externally through the brain. If you hooked up/unhooked the jumper cables improperly it might cause electrical issues.
IIRC it is; + cable on good battery first. Then + cable on dead battery. Then - cable on good battery and then........- cable on good unpainted surface of the dead battery's vehicle. The reverse order for taking them off when the dead vehicle fires up.
I usually do this then fire up the good vehicle....and wait for a full ten minutes. This give the dead battery to begin to accept a charge. They actually resist charging when they are real dead.
Doing it the wrong way could fry 'things' on the good vehicle that do not 'like' high resistance or shorting.
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"If we cannot afford to take care of Veterans, then we should stop making them."
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