GxT Ferret 54 ENGINE DIAGNOSTIC CENTER - Manual (Page 48)

ELECTRICAL
STARTING / CHARGING
HISTORY
Press ELECTRICAL, SELECT Starting/
Charging History, and press NEXT.
An electrical power system test of the engine
is the primary feature of this sequenced
procedure. Performance measurements of
the alternator, battery, and starter allow
comparison to ratings.
This test records battery voltage and amps
while the starter cranks the engine for 15
seconds. Then there is a wait to check
battery recovery time, followed by a
measurement of the charging current when
the engine is run at high idle.
A screen may prompt you to zero the amp
probe. Follow the on-screen instructions. For
accurate results, turn off all lights and
accessories. Be sure the vehicle doors are
closed, as the current drawn by dome and
courtesy lights is significant and may
invalidate the test results.
If a DIS or Diesel engine type was selected
during
Engine Setup, the Diagnostic Center
will prompt you to disable the fuel supply to
prevent the engine from starting during
cranking. Use the recommended method to
disable the engine for compression cranking
tests, from the vehicle service manual. This
is usually done by unplugging the power wire
or fuse to the fuel injectors or ignition coils.
Run the engine until it quits, to verify that fuel
is cutoff.
On a distributor engine, with the Coil Primary
Clip connected, the Diagnostic Center will
suppress the ignition during cranking. If, for
some reason the Diagnostic Center has
difficulty suppressing a particular ignition, the
disable fuel prompt will appear.
Begin cranking when prompted. After 15
seconds, the Diagnostic Center will prompt
you to stop cranking and turn the ignition key
off. (If the battery voltage drops below 9.6
volts during the test, it is too low to continue,
and the test will be aborted before 15
seconds have passed.)
When the operator stops cranking, a waiting
period begins while voltage recovery time of
the battery is checked. Good batteries will
spring back in 1 or 2 seconds. Worn out or
undercharged batteries need over 10
seconds to recover. Make sure all battery
drains such as dome lamps are off during
this test. Keep doors closed.
The Diagnostic Center may shut down the
Gas Detector pumps and the LCD
backlighting during this test to reduce power
consumption.
Restore fuel or ignition power, as necessary,
and be ready to start the engine when
prompted. Run the engine over 1500 RPM
to ensure the regulator has “kicked in”, so
that charging current can be measured.
The Diagnostic Center will then prompt you
to SELECT a temperature range to be used
in the calculation of the battery’s Cold
Cranking Amp (CCA) rating. Choose the
temperature of the battery electrolyte, which
may be different from shop temperature if the
battery has recently been brought in from a
very hot or very cold environment just prior
to testing.
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