C.E. Niehoff & Co. C510/C540 Troubleshooting Guides - Manual (Page 4)

Page 4 TG1B
Identifi cation Record
Alternator model number______________________
Rectifier model number _______________________
Regulator model number ______________________
Setpoints listed on regulator ___________________
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, recti-
fier, or regulator.
Check: loss of phase winding. See
Chart 1, page 5.
Check: wrong regulator.
Check: high regulator setpoint.
Check: defective regulator.
Check: alternator.
Check: broken drive belt.
Check: battery voltage at alternator
output terminal.
Check: defective alternator, recti-
fier, and/or regulator.
Low Voltage Output
High Voltage Output
No Voltage Output
Preliminary Check-out
Check symptoms in Table 1 and correct if necessary.
Tools and Equipment for Job
• Digital Multimeter (DMM)
• Ammeter (digital, inductive
• CEN Regulator Bypass Adapter A10-129
• Jumper wire
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Basic Troubleshooting
1. Inspect charging system components for damage
Check connections at B– cable, B+ cable, rectifier
harness, and regulator harness. Also check connec-
tions at regulator terminal wiring from regulator to
vehicle components. Repair or replace any damaged
component before electrical troubleshooting.
2. Inspect vehicle battery connections
Connections must be clean and tight.
3. Check drive belt
Repair or replace as necessary.
4. 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.
5. Determine if battery isolator is used in
charging circuit
Check vehicle wiring diagram. If so, the isolator
must be jumpered out before troubleshooting. See
Chart 1 on page 5 for details.
6. 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.
7. 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.
If voltage is at or below regulator setpoint, let
charging system operate for several minutes to
normalize operating temperature.
8. 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.
9. Battery is considered fully charged if charge
voltage is at regulator setpoint and charge amps
remain at lowest value for 10 minutes.
10. If charging system is not performing properly,
go to Chart 1 on page 5.
CAUTION
Failure to check for the following
conditions will result in erroneous
test results in the troubleshooting
charts.
NOTICE
Section C: Basic Troubleshooting
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