GxT Ferret 54 ENGINE DIAGNOSTIC CENTER - Manual (Page 62)

5-1
Measurement Typical Readings Interpretation
Battery Volts 12.4 to 12.8 Volts Checks battery state of charge.
(Engine Off) Below 12.3V, charge is low, or load may be on.
Ignition Energy More than 20 mVSec Shows that there is coil energy available to
(Cranking) start the engine.
Battery Volts 13.2 to 15.2 Volts Shows the voltage regulator setting and
(Engine Running) if the alternator functions.
Amps Ripple None If alternator has a bad diode or stator,
(Engine Running) a message will appear.
Ignition Energy 35-55 mVSec Checks for faulty coils, and driver modules.
(Engine Running)
Dwell 60% w/ Ballast Adjust as necessary.
3 to 4 mSec, current limited Checks ignition modules.
Dwell Variation 3.0
°
or less Checks primary ignition system performance.
(Engine Running) Test from Idle to Cruise RPM.
Timing Variation 3.0
°
or less Shows ignition timing irregularity if too high.
(Engine Running)
Driver Voltage Electronic less than 1.5V Shows coil driver module, and module
(Engine Running) Points less than 0.3V ground resistance if too high.
Coil Oscillations Electronic 1 to 4 Osc Checks for shorts in coil insulation or
(Engine Running) Points 4 to 8 Osc connected components.
TYPICAL READINGS
Most tests produce relative readings that can be reviewed for consistency among cylinders or
coils, and judgements can be made as to whether a component is faulty. Absolute readings
vary from engine to engine. The readings listed here are typical for many common engines,
but should be compared to the manufacturer's specifications before extensive repair work is
undertaken.
DISTRIBUTOR ENGINES
HARD ST
ART
CHARGING
(Engine Running)
IGNITION PRIMAR
Y