If the potential (votage drop) of the terminal "B" or ground harness is over threshold value, Impossible cranking could occur. Check the starter by measuring the potential(Votage drop).
IG "START"
Measure the potential (Voltage drop) between terminal B of starter and battery (+) terminal.
Probe(+) : Battery (+) terminal
Probe(-) : Terminal "B" of the starter
Specification : Below 0.5V
Is the potential (Voltage drop) within Specification?
YES
Go to "Starter Chassis ground Inspection" procedure.
NO
Replace harness between battery(+) terminal and terminal B of starter.
IG "START"
Measure potential (Voltage drop) between battery(-) terminal and chassis ground.
Probe(+) : Battery (-) terminal
Probe(-) : Chassis ground
Specification : Below 0.5V
Is the potential (Voltage drop) within Specification?
YES
Faulty starter or Engine stuck
NO
Faulty harness between battery (-) terminal and chassis ground
Check the connecting condition of the starter.