Troubleshooting - Cub Crafters CC11-100 Maintenance Manual

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TROUBLESHOOTING

PROBLEM
No Operation
Low Voltage
High Voltage
Refer to Figure 5.4.14.1, Figure 6.3.17.4, and use a high-impedance (preferably digital)
volt/ohmmeter (DVM) to make the following checks.
THE ENGINE SHOULD NOT BE RUNNING AND THE MAGNETOS SHOULD BE OFF!
(a) Turn all switches off. Use the lowest resistance scale on the DVM. Check the
resistance between the battery negative (-) terminal and both pin - of the
regulator and the engine case. Measurements over 0.5 Ohm in either cause
should be investigated. If this is the case, check the engine ground strap, battery
ground strap, and regulator ground wire for loose or contaminated connections,
broken conductors or bad crimp joints. If these measurements are less than 0.5
Ohm, any of these three points may be used as reference (-) for the following
measurements.
(b) Turn on the master switch. Measure the voltage on the battery bus and on pin +
of the regulator. The voltages should be equal, within 0.2 volts. A difference of
more than 0.2 volts may be caused by a bad breaker.
(c) Intermittent problems are the hardest to find. Bring small test wires into the
cockpit from two or three of the points mentioned above to allow them to be
monitored with the DVM while running the electrical systems. Double check all
screw terminals for security. Try a 5 pound pull test on all crimp joints and make
sure that the terminals are crimped on the wire, not the insulation.
Manual number SC10000AMM
Date: 08/02/2010
CUB CRAFTERS, INC.
CC11-100 MAINTENANCE MANUAL
PROBABLE CAUSE
Engine speed too low
Blown fuse(s)
Bad Wire Connections
Shear coupling broken
Regulator Faulty
Alternator Faulty
Engine speed too low
Very Low Battery
Bad battery (shorted cell)
Load exceeds alternator output
Bad battery (open)
Bad regulator
WARNING
REMEDY
Check for output at higher speed
Replace fuse(s)
Replace bad connectors
Replace shear coupling
Replace regulator
Overhaul or replace alternator
Increase engine speed
Charge battery
Replace battery
Decrease load or increase
engine RPM
Check connections and/or
replace battery
Replace Regulator
6.3.17
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