DHC BT797 Manuel De L'utilisateur page 11

HIGH CHARGING VOLTS WHEN TEST AT
IDLE
The voltage output from the alternator to the
battery exceeds the normal limits of a functioning
regulator. Check to ensure there is no loose
connection and the ground connection is normal.
If there is no connection issue, replace the regulator. Since most alternators
have the regulator built-in, this will require you to replace the alternator. The
normal high limit of a typical automotive regulator is 14.7 volts +/- 0.05. Check
manufacturer specifications for the correct limit, as it will vary by vehicle type
and manufacturer.
CHARGING SYSTEM NORMAL WHEN TEST
AT IDLE
The system is showing normal output from the
alternator. No problem is detected.
LOW CHARGING VOLTS WHEN TEST
AT IDLE
The alternator is not providing sufficient current
to the battery. Check the belts to ensure the
alternator is rotating with engine running.
If the belts are slipping or broken, replace the 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. If the belts and
connections are in good condition, replace the alternator.
6. Press «ENTER» for the charging system with
accessory loads. Turn on the blower to high
(heat), high beam headlights, and rear defogger.
Do not use cyclical loads such as air conditioning
or windshield wipers.
7. When testing older model diesel engines, the
users need to run up the engine to 2500 rpm for
15 secs.
8. Press «ENTER» to read the ripple from the charging system to the battery.
One of the three testing results will be displayed along with the actual testing
ALT. IDLE VOLTS
ALT. IDLE VOLTS
xx.xx V NORMAL
ALT. IDLE VOLTS
TURN ON LOADS
PRESS ENTER
RUN ENGINE UP
TO 2500RPM 15
11
11
11
xx.xx V HIGH
xx.xx V LOW
SEC