11
Midtronics B.V. Hoofdveste 6 3992 DG HOUTEN
www.midtronicseurope.com
CHAPTER 5:
SYSTEM TEST
ALTERNATOR TEST RESULTS
Decision
Action
NO
PROBLEMS
The system is showing normal output
from the alternator. No problem
detected.
NO VOLTAGE
The alternator is not providing charging
current to the battery.
•
Check the belts to ensure the
alternator is rotating with the engine
running. Replace broken or slipping
belts and retest.
•
Check all connections to and
from the alternator, especially
the connection to the battery. If
the connection is loose or heavily
corroded, clean or replace the cable
and retest.
•
If the belts and connections are in
good working condition, replace
the alternator. (Older vehicles use
external voltage regulators, which
may require only replacement of the
voltage regulator.)
LOW
VOLTAGE
The alternator is not providing enough
current to power the system’s electrical
loads and charge the battery.
•
Check the belts to ensure the
alternator is rotating with the engine
running. Replace broken or slipping
belts and retest.
•
Check the connections from the
alternator to the battery. If the
connection is loose or heavily
corroded, clean or replace the cable
and retest.
HIGH
VOLTAGE
The voltage output from the alternator to
the battery exceeds the normal limits of a
functioning regulator.
•
Check to ensure there are no loose
connections and that the ground
connection is normal. If there are no
connection problems, replace the
regulator. (Most alternators have
a built-in regulator requiring you
to replace the alternator. In older
vehicles that use external voltage
regulators, you may need to replace
only the voltage regulator.)
DIODE DECISIONS
Decision
Action
EXCESSIVE
RIPPLE
One or more diodes in the alternator
aren’t functioning or there’s stator
damage, which is shown by an excessive
amount of AC ripple current supplied to
the battery.
•
Make sure the alternator mounting is
sturdy and that the belts are in good
shape and functioning properly. If
the mounting and belts are good, re-
place the alternator.
PHASE OPEN
The Tester has detected an open phase
within the alternator. Replace the
alternator.
DIODE OPEN
The Tester has detected a open diode
within the alternator. Replace the
alternator.
DIODE
SHORT
The Tester has detected an shorted
diode within the alternator. Replace the
alternator.
3.
Now REV ENGINE WITH LOADS OFF FOR 5 SECONDS. If
the rev is detected the analyzer will show: ACQUIRING
DATA...HOLD ENGINE RPM until the data are acquired.
Tester now shows: ENGINE REV DETECTED, IDLE ENGINE.
4.
TESTING ALTERNATOR AT IDLE, LOADS OFF: The analyzer
will next test the engine at idle for comparison to other
readings, and then test the diode ripple. Excessive ripple
usually means one or more diodes have failed in the al-
ternator or there is stator damage.
5.
TURN HIGH BEAMS AND BLOWER MOTOR ON, IDLE EN-
GINE: After a few seconds, the Tester will ask you to turn
on the accessory loads. It will determine if the charging
system is able to provide enough current for the de-
mands of the electrical system.
IMPORTANT: Turn on the high-beam headlights,
the blower to high and the rear defogger. Do
not use cyclical loads such as air conditioning or
windshield wipers.
6.
TESTING ALTERNATOR AT IDLE, LOADS ON: The analyzer
will determine if the charging system is able to provide
sufficient current for the demands of the vehicle’s elec-
trical system.
7.
Now once more you are requested to REV ENGINE WITH
LOADS ON, if the rev is detected again, the tester will
show: ACQUIRING DATA...HOLD ENGINE RPM until the
analyzer shows ENGINE REV DETECTED, IDLE ENGINE.
8.
ANALYZING CHARGING SYSTEM DATA: The Tester is com-
pleting its final analysis of the charging system data.
9.
TURN OFF LOADS AND ENGINE: Press the NEXT soft key
to display the results. In case you are using an Amp clamp
10.
DRAIN TEST or DRAIN CURRENT: This will be asked ONLY
when the Amp clamp is in use. Depending on whether or
not using the integrated clamp, press NEXT to proceed
drain test or fill in the current as displayed on the Amp
clamp.
