M1507

2022-03-16

M1507: LOW/NO CHARGING DIAGNOSTICS
Motorcycles Affected

Reason for Revision

2014 - 2020 Sportster platform.

Refer to Table 1.

2017 - 2021 Touring and Trike platform.
Table 1. Document History
Date
2022-03-16
2021-06-04
2020-01-24
2020-01-17

2018 - 2021 Softail platform.

Revision Description
Added DC Lead part numbers for Touring and
Softail
* Updated
Added Touring, Trike and Softail platforms
* Updated
Main fuse
* Updated
Initial release

Markets Affected
All markets are affected.

Required Dealer Action
Use the new diagnostics on all affected platforms.
Replace the LOW OR NO CHARGING symptom based
diagnostic in the electrical diagnostic manual with the updated
and new sections.

Purpose for Service Bulletin
To inform the dealers of updated and new symptom-based
diagnostics for the low or no charging symptom.

LOW OR NO CHARGING
em01654

BK
BK

BK
BK

[47B]
[47A]

Stator

1 2
1 2

Voltage
Regulator
N P

Fuse Block
[64B]
Main 40A

N P
BK
R

[77A]
[77B]

A

B

R

R

BK

R

R

Battery
GND 1

Battery
Ground

BCM

Figure 1. Charging System Circuit

NOTE
In the interest of preserving customer safety and satisfaction, always check for outstanding recalls whenever any motorcycle is brought into your dealership for either maintenance or service.
ROUTING

INITIAL HERE

SERVICE
MANAGER

SALES MANAGER PARTS MANAGER

WARRANTY
PROCESS
MANAGER

LEAD TECHNICIAN TECHNICIAN NO. 1 TECHNICIAN NO. 2 TECHNICIAN NO. 3 RETURN THIS TO

NOTE
When a connector is disconnected always inspect the socket
and pin terminals for damage or corrosion.

3.

Is resistance less than 0.5 Ω?

1153256

1. Battery Test
1.

Perform battery test. See BATTERY TESTING.

2.

Did battery pass test?

+

-

(+)

(–)

a. Yes. Go to Test 2.
Figure 2.

b. No. Replace battery.
a. Yes. Go to Test 7.
2. Off Idle Voltage Test
1.

Start engine and run at 3,000 rpm for 30 s.

2.

With the engine still running at 3,000 rpm, test battery
voltage.

3.

Is voltage above 14 V?
a. Yes. Go to Test 8.
b. No. Go to Test 3.

b. No. Repair open wire between voltage regulator [77B]
terminal (+) and battery.
7. Voltage Regulator Ground Circuit Test
NOTE
Voltage regulator ground must have a clean, tight connection
for proper grounding.
1.

See Figure 3. Test resistance between [77B] terminal (-)
and ground 1.

2.

Is resistance less than 0.5 Ω?

3. AC Output Test
1.

Perform Alternating Current (AC) output test. See
BATTERY CHARGING TESTS.

2.

Did output test pass?

1167263
+

-

a. Yes. Go to Test 6.

(+)

(–)

b. No. Go to Test 4.
4. Stator Test
1.

Perform stator test. See BATTERY CHARGING TESTS.

2.

Is the stator good?

Figure 3.
a. Yes. Go to Test 8.

a. Yes. Go to Test 5.

b. No. Repair open wire between voltage regulator [77B]
terminal (-) and ground 1 (BK) wire.

b. No. Replace stator.
5. Rotor Inspection Test

8. Voltage Regulator [77] Test

1.

Turn IGN OFF.

1.

If necessary: Connect all connectors.

2.

Inspect rotor magnets for damage.

2.

Start engine and run at 2,000 rpm for 30 s.

3.

Remove rotor assembly and inspect rotor and shaft splines
for excessive wear.

3.

With the engine still running at 2,000 rpm, test battery
voltage.

4.

Verify stator bolts have not backed out and contacted rotor.

4.

5.

Is rotor in good condition?

While testing battery voltage, perform a wiggle test on
voltage regulator [77].

5.

Did voltage stay at or fluctuate below 13.5 V?

a. Yes. Go to Test 6.

a. Yes. Connector socket issue. See .

b. No. Replace rotor.

b. No. Go to Test 9.

6. Voltage Regulator Power Circuit Test
1.

See Figure 1. Disconnect voltage regulator [77].

9. Voltage Regulator [47] Test

2.

See Figure 2. Using TEST CONNECTOR KIT (PART
NUMBER: HD-41404), test resistance between [77B]
terminal (+) and battery.

1.

With the engine still running at 2,000 rpm, test battery
voltage.

2.

While testing battery voltage, perform a wiggle test on
voltage regulator [47].

3.

Did voltage stay at or fluctuate below 13.5 V?
a. Yes. Connector socket issue. See .
b. No. Charging system working properly.

2/3

M1507

CONNECTOR SOCKET ADJUSTMENT
1.

Clean both pins and sockets with contact cleaner.

2.

Test socket terminal.
a.

Using GREEN probe from test connector kit.
Special Tool: TEST CONNECTOR KIT (HD-41404)

3.

b.

Insert and remove probe from socket terminal of
connector.

c.

Slight drag should be felt throughout the complete
terminal.

d.

Drag is felt: No adjustment necessary.

e.

No drag is felt: Go to Step 3.

Adjust socket terminal.
a.

Remove main fuse.

b.

Use a small flat tipped screw driver to slide down the
length of the socket, 90° from terminal gap.

c.

Rock and twist screw driver so that the terminal
tightens along the entire length of terminal.

NOTE
Use caution not to tear or damage the socket
housing.

4.

5.

d.

Test drag using GREEN probe. Adjust if necessary.

e.

Verify that socket terminal is even with end of the
connector housing.

f.

Install main fuse.

Perform wiggle test.
a.

Passed wiggle test: Repair completed, charging
system working properly.

b.

Failed wiggle test: Go to Step 5.

Failed wiggle test voltage of:
a.

Fluctuating voltage below 13.5 V on [77]: Replace
[77] assembly Sportster (74120-08), Touring
(69201423) and Softail (69201760A).

b.

Fluctuating voltage below 13.5 V on [47]: Replace
stator.

c.

No voltage difference between engine running or
engine off at battery: Replace voltage regulator.

M1507

3/3