C.E. Niehoff & Co. N1607/N1611/N3215B/N2013 Troubleshooting Guides - Manual (Page 4)

Page 4 TG56B
Section B: Basic Troubleshooting
Basic Troubleshooting
1. Inspect charging system components
Check connections at ground cables, positive
cables, and regulator harness. Repair or replace
any damaged component before troubleshooting.
2. Inspect battery isolator connections
Connections must be attached properly and
clean and tight. See Figure 4, page 3.
3. Inspect connections of vehicle batteries
Connections must be clean and tight.
4. Determine battery type, voltage and state
of charge
Batteries in each bank must be all the same type
for system operation. If batteries are discharged,
recharge or replace batteries as necessary. Electri-
cal system cannot be properly tested unless batter-
ies are charged 95% or higher. See page 1 for
details.
5. Connect meters to alternator
Connect red lead of DMM to alternator 28 V B+
terminal and black lead to alternator B– termi-
nal. Clamp inductive ammeter on 28 V B+ cable.
6. Operate vehicle
Observe charge voltage.
If charge voltage is above
32 volts, immediately shut
down system. Electrical
system damage may occur if
charging system is allowed
to operate at excessive
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 in each circuit
Charge voltage should increase and charge
amps should decrease. If charge voltage does not
increase within ten minutes, continue to next step.
8. Batteries are considered fully charged if charge
voltage is at regulator setpoint and charge amps
remain at lowest value for 10 minutes.
9. If charging system is not performing properly,
go to page 5.
SYMPTOM ACTION
TABLE 1 – System Conditions
Check: loose drive belt; low bat-
tery state of charge.
Check: current load on system
is greater than alternator
can produce.
Check: defective wiring or poor
ground path; low regu-
lator setpoint.
Check: defective alternator
and/or regulator.
Check: wrong regulator.
Check: high regulator setpoint.
Check: defective regulator.
Check: alternator.
Check: presence of energize
signal.
Check: battery voltage at alter-
nator output terminal.
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)
• Jumper wires
Identification Record
List the following for proper troubleshooting:
Alternator model number ________________________
Regulator model number ________________________
Setpoint listed on regulator _____________________
Battery isolator model number ___________________
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CAUTION