Chapter 9: Cable Drop Test - Midtronics INTELLECT EXP HD Instruction Manual

Chapter 9: Cable Drop Test

If the test results for the starter or chargng systems ndcate that there may be a problem, you may want
to perform the Cable Drop Test to determne f t s due to worn cables or bad connectons between the
battery and the alternator or starter. Worn cables or bad connectons create hgher resstance, whch
causes a drop across the crcut. The voltage drop reduces current carryng capablty that dsplays the
same symptoms as a weak alternator or starter and causes premature battery falure.
There s no need to run the engne. The Cable Drop Test uses Mdtroncs' conductance technology to
send a sgnal through the crcut to the component under test. The EXP then smultaneously calculates
voltage drop on the postve (+) and negatve (–) sdes of the crcut as well as the total voltage drop. The
amperage range for each of the four tests s 0 to 1000 A. When you change the settng from the factory
defaults, the EXP wll store your settng n memory for your next test.
There are four preset tests for components up to 1000 amps:
Component
Battery Ground
Starter Crcut
Alternator Crcut
Chasss Ground
Other Crcut (a crcut of your choce)
The test requres two test lead connectons, as shown n the llustraton below.
1. Connect the battery test leads at the component's output lead (the B+ or output screw on
the alternator) and the component's housng as ground.
2. Connect the DMM test leads at the battery termnals.
NOTE: The test requres a complete crcut. If you are testng a system wth a remote solenod, you
can test from the battery to the solenod, but not from the battery to the starter.
IMPORTANT: For accurate results the battery should be good and fully charged before you test.
Chapter 9: Cable Drop Test
Red
+
Battery
–
Black
DMM Test Lead
Default Settings
Auto Van
80 A
150 A
80 A
—
10 A
Red
R
1
Component
Under
Test
R
2
Black
Battery Test Lead
Truck
—
500 A
135 A
135 A
10 A