C.E. Niehoff & Co. C711/C712 Troubleshooting Guides - Manual (Page 3)

Page 3
TG0009A
C. E. Niehoff & Co.
BRUSHLESS ALTERNATORS
D. Basic Troubleshooting
1. Inspect charging system components Inspect charging system components Inspect charging system components Inspect charging system components Inspect charging system components
for damage
for damage for damage for damage for damage
Check connections at B– cable, B+ cable, and
regulator harness. Repair or replace any dam-
aged component before troubleshooting.
2. Inspect vehicle battery connections Inspect vehicle battery connections Inspect vehicle battery connections Inspect vehicle battery connections Inspect vehicle battery connections
Connections must be clean and tight.
3. Determine battery voltage and state of charge Determine battery voltage and state of charge Determine battery voltage and state of charge Determine battery voltage and state of charge Determine battery voltage and state of charge
If batteries are discharged, recharge or replace
batteries as necessary. Electrical system cannot
be properly tested unless batteries are charged
95% or higher.
4. Determine if battery isolator is used Determine if battery isolator is used Determine if battery isolator is used Determine if battery isolator is used Determine if battery isolator is used in in in in in
charging circuit charging circuit charging circuit charging circuit charging circuit
Check vehicle wiring diagram. If so, you must
jumper out isolator before troubleshooting. See
Chart 1 on page 4 for details.
5. Connect meters to alternator Connect meters to alternator Connect meters to alternator Connect meters to alternator Connect meters to alternator
Connect red lead of DMM to alternator B+
terminal and black lead to alternator B–
terminal. Clamp inductive ammeter on B+ cable.
6. Operate vehicle Operate vehicle Operate vehicle Operate vehicle Operate vehicle
Observe charge voltage.
If charge voltage is above
16.5 volts, immediately
shut down system. Electrical system damage may occur if
charging system is allowed to operate at high voltage. Go to
Table 1 at left.
If voltage is at or below regulator setpoint, let
charging system operate for several minutes to
normalize operating temperature.
7. Observe charge volts and amps Observe charge volts and amps Observe charge volts and amps Observe charge volts and amps Observe charge volts and amps
Charge voltage should increase and charge amps
should decrease. If charge voltage does not
increase within ten minutes, continue to next
step.
8. Battery Battery Battery Battery Battery is considered fully charged if charge
voltage is at regulator setpoint and charge amps
remain at lowest value for 10 minutes.
9. If charging system If charging system If charging system If charging system If charging system is not performing properly,
go to Chart 1, page 4.
CAUTION
Section 2: Basic Troubleshooting
SYMPTOM ACTION
TABLE 1 – System Conditions
Check: loose drive belt; low
battery state of charge.
Check: current load on
system is greater than
alternator can produce.
Check: defective wiring or
poor ground path; low
regulator setpoint.
Check: defective alternator
and/or regulator.
Check: wrong regulator.
Check: high regulator set-
point.
Check: defective regulator.
Check: alternator.
Check: broken drive belt.
Check: battery voltage at
alternator output terminal.
Check: defective alternator
and/or regulator.
Low Voltage Output
High Voltage Output
No Voltage Output
C. Preliminary Check-out
Check condition of items in Table 1 and correct if
necessary.
A. Tools and Equipment for Job
• Digital Multimeter (DMM)
• Ammeter (digital, inductive)
• CEN Regulator Bypass Adapter A10-129
• Jumper wire
• 12 V test light
B. Identification Record
Complete the following for proper troubleshooting:
Alternator model number ______________________
Regulator model number _______________________
Setpoints listed on regulator ___________________
o
o
o