S | Technical Service Bulletin

Technical Service Bulletin: TSB230103 Released Date: 08-Jun-2023
Campaign #5296 - HGJAD, HGJAE, HGJAF, HGJAK Voltage Regulator Overheating Issue

Campaign #5296 - HGJAD, HGJAE, HGJAF, HGJAK Voltage
Regulator Overheating Issue

Warranty Statement

The information in this document authorizes specific changes to the repair practice for failures covered under product warranty
coverages.

Contents

Product Affected

« HGJAD, Specs A-M
« HGJAE, Specs A-M
e¢ HGJAF, Specs A-M
« HGJAK, Specs A-M

Issue

A batch of voltage regulators PN A071S740 installed on generator sets built between October 2022 and March 2023 are missing a
current limiting feature that may cause voltage regulator overheating issues.

Symptoms:

« Damaged voltage regulator from overheating

¢ Melted wires/terminals
¢ Possible voltage regulator miswiring.

Root Cause:

¢ Abatch of generator sets built between October 2022 and March 2023 shipped out with voltage regulator PN A071S740
missing a current limiting feature.

Verification/Confirmation

To verify voltage regulator overheating issue, inspect any Commercial Mobile HGJAx units built between October 2022 and March
2023:

- If Voltage Regulator PN A071S740 is installed, order a new voltage regulator PN 0305-1006 for part replacement.

- If Voltage Regulator miswiring is found, rewire as indicated in the Service Instructions section

17101921

Figure 1, Shows Defective Voltage Regulator (Fenix) PN A071S740 on the left vs. Recommended Voltage Regulator (PVL) PN
0305-1006 on the right

Resolution

Inspect any suspect units built between October 2022 and March 2023 and replace faulty part PN A071S740 with part PN 0305-
1006. Refer to Service Instructions for procedure.

Description of Change

This document informs the field of repair instructions to address voltage regulator overheating issues for units built between October
2022 and March 2023

Service Instructions

Procedure for Voltage Regulator Replacement:
1. Unbox or remove generator set from coach.

2. Unscrew the top cover screws (x4).

17101922

Figure 2, Top Cover Screw Locations

3. Pull on connector body to remove all three wire terminals from the voltage regulator. Make sure there is no stress on wire.

17101923

Figure 3, Wire Removal

4. Unscrew the M6 screws (x2) to remove the voltage regulator. Retain screws for reuse

17101924

Figure 4, Voltage Regulator Removal

5. Check the cold resistance of the stator against value in the service manuals A035D011 and 0983-0501 (for HGJAD-F units),
A049V684 (for HGJAK units) using multimeter. Check the entrance of the stator for any visual damage.

17101925

Figure 5, Use a multimeter for cold resistance measurement

6. Inspect all three wires for damage. In case of any damage on the wires or/and terminals, repair or replace as needed.

17101926

Figure 6, Visual example of damaged wires and miswired terminals

7. Order a new voltage Regulator PN 0305-1006 and mount it to same location using the same M6 screws. Follow orientation as
shown in figure 7 (Cummins logo sign facing outwards). Tighten both screws at Torque 8.7 Nm to 13 Nm (6.4 - 9.6 ft-lbs.)

17101927

Figure 7, PVL Voltage Regulator Orientation with Cummins logo facing outward

17101928

Figure 8, Voltage Regulator Installation

8. Connect the wire terminal to the new voltage regulator. Make sure Blue terminal goes to B+ and two yellow terminals to AC.

17101929

Figure 9, PVL Voltage Regulator Wiring

9. Reinstall generator set top cover. Torque to 8.7Nm to 13 Nm (6.4 - 9.6 ft-lbs.)
10. Reinstall generator back into the vehicle or into package if uninstalled.

11. Inspect defective voltage regulator PN A071S740 for visual damage such as discoloration, melted wires or terminals, etc. as
shown in Figure 6.

11a. If visual damage not found, scrap defective part.

11b. If visual damage found, ship defective voltage regulator back to the CPG-Fridley factory for analysis using the shipping details
below.

Shipping Address:

Cummins Power Generation

7033 Central Ave

Fridley, MN 55432

ATTN: Timothy Jensen.

Campaign Details:

Expiration Date: May 31, 2025

Account Code: 65

Authorization Code: 5296

Failcode: OR-VR-MW

Parts Replacement: Replace Voltage Regulator PN A071S740 with PN 0305-1006.
SRTs:

a) To be used for units installed into vehicle applications (3hrs):
00-901 (0.3hrs): Administrative time-open/close repair (Shop)

00-1AE (2.2hrs): Generator Set Complete Remove and Install

99-999 (0.5hrs): Generator Set Enclosure Removal and Install

Includes the following additional steps:

(1) Inspect Voltage Regulator for proper part number.

(2) Voltage Regulator Remove and Install

(3) Repair any damaged wiring.

b) To be used for units not installed into vehicle application (1.2 hrs):
00-90F (0.2hrs): Administrative Time - Travel

00-902 (0.3hrs): Administrative Time — Out of Shop

00-90M (0.2hrs): Technician Administrative Time — Multiple Failures/Units

99-999 (0.5hrs): Generator Set Enclosure Removal and Install
Includes the following additional steps:

(1) Inspect Voltage Regulator for proper part number

(2) Voltage Regulator Remove and Install

(3) Repair any damaged wiring.

Note: Generator sets that may exhibit this symptom were manufactured between October 2022 and March 2023 as indicated by the
generator set serial number. Date of manufacture is indicated by the first three characters of the generator set serial number.
Generator sets with serial numbers beginning with J22 through C23 may be affected.

Service Parts Availability

Service parts are available. See Table 1 for part numbers

Table 1, Service Parts

a oa Recommended Part
Part Description Existing Part Number | Obsolete Superseded :

Number for repair
Voltage Regulator A071S740 N/A N/A 0305-1006

Document History

Date Details
2023-5-11 Module Created

Last Modified: 08-Jun-2023