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Connect:
•
Black test probe to the negative (-) battery post.
•
Red test probe to the point on the fender, fire wall, or vehicle frame where the accessory ground is
fastened.
Press the “
REC
” button (selects the MAX.MIN.AVG function).
Turn on all the accessories (headlights, A/C fan, defroster, windshield wiper, etc.).
Disable the ignition so the engine can’t start and crank the engine for four to five seconds.
This connection has two connectors, one wire, one ground and one cable terminal-tobattery post; a voltage drop
of more than 0.5V indicates a poor ground circuit.
Clean and inspect the battery cable connections and the ground and test again.
NOTE:
Repeat the test after the engine has thoroughly warmed up. Heat expansion may change voltage drop.
Battery Ground to Starter Solenoid (+) Voltage Drop Test
This test checks for battery power efficiency to the starter solenoid. Measure the voltage drop between the
battery post and the connecting cable, the solenoid post (+), and the wire that attaches to it.
Red
Black
Solenoid
12V Battery
Starter Moto
r
Meter setup to check voltage drop:
•
Set the rotary switch to voltage ( ) setting.
•
Press the “
DC/AC
” button until “ ” appears on the display.
