1

Part Number

Description

081034

Loctite -243 Medium

Figure 8: Upper ESS Assembly Installation Location Reference.

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30. Locate the coolant line supply and return hose connections at each ESS and re-install the restrictor/orifice in
the inlet hose. Reconnect the coolant hoses and install the existing clamps from each ESS unit. Torque to 80
IN-LBS. Allow clamps to rest for 30 min and re- torque to 80 IN-LBS. Apply torque marks after torquing. See
Figure 9.
31. Re-connect the LV wiring connectors from each ESS unit. See Figure 9.
LV Connections

Torque Clamps Dry to
80 IN-LBS. Let Rest
for 30 Min and Retorque to 80 IN-LBS.

Coolant Hose
Supply and
Return
Connections
Figure 9: Upper ESS Coolant Line and LV Re-connection Location Reference.

32. Connect the ground cable to the ESS unit using the correct hardware.
A. For units with a ground stud application place cable on the ground stud with the existing flat washer and
Nylon nut Ref item #3 and torque nut to 17 FT-LBS. Apply torque marks after torquing. See Figure 10.
B. For units with the ground cable bolt mounting secure the ground cable to the unit with the existing washer
and ½ IN bolt ref item #4 and Torque to 22 FT-LBS. Apply torque marks after torquing. See Figure 10.





NOTE: Do not use mounting bolts longer than ½ IN.
NOTE: Ensure to validate the torque based on stud or bolt application.
NOTE: Apply item #6 Anti-corrosion compound to ground connections.
#4 Bolt

½” Bolt Application
Torque Bolt to 22 FT-LBS

#3 Nylon Nut

Ground
Cable Stud
Application
Torque Nut to
17 FT-LBS.

Figure 10: Upper ESS Assembly Ground Stud and HV Cable Re-installation Location Reference.

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33. Place the charge rail assembly on the roof and re-install the existing flat washer and item #3 nylock nuts
mounting to the roof structure and torque to 22 FT-LBS. Apply torque marks after torquing. See Figure 11.
34. Re-connect the charge rail ground cable to the body ground using existing washers and item #3 nylock nuts
and torque to torque to 22 FT-LBS. Apply torque marks after torquing. Applying item #6 Anti-corrosion
compound. See Figure 11A.
35. Re-connect the charge rail box ground to the body ground using existing washers and item #3 nylock nuts
and torque to torque to 22 FT-LBS. Apply torque marks after torquing. Applying item #6 Anti-corrosion
compound. See Figure 11A.

Re-Connect
Grounds
Applying
Item #6 and
Torque to
22 FT-LBS

Item

Re-install
Charge
Rail
Assembly
Mounting
Hardware
to Roof
Structure
and
Torque to
22 FT-LBS

Part Number

Description

3

42N06000

Nut 3/8-16 UNC Nylon Lock SST

6

8111767

Anti – Corrosion Compound NYK-77

Figure 11A: Charge Rail Installation Location Reference.

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36. Re-connect HV cable quick disconnects on the street side to appropriate charge box receptacles. See Figure
11B.
37. Re-connect and secure the WLAN antenna to the bus harness. See Figure 11B.
38. Re-install the HV cable clamps on the street side of charge rail with the existing hardware and the nylon lock
nuts item #8 and torque hardware to 6 FT-LBS. Apply torque marks after torquing. See Figure 11B.

Re-connect
and Secure
WLAN
Harness

Re-install HV Cable
Clamps replacing Item
#8 Nylock Nuts And
Torque to 6 FT-LBS

Item
8

Part Number

Description

42N04000

Nut Nylon Lock ¼-20

Figure 11B: Charge Rail Installation Location Reference.

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39. Re-connect the curb side and street side heater wiring to the charge rails using the existing hardware applying
item #6 Anti-corrosion compound and torque to torque to 22 FT-LBS. Apply torque marks after torquing. See
Figure 11C.
40. Re-connect the temp sensor from under the DC charge rail box on the street side and all low voltage wiring.
See Figure 11C.
41. Re-install clamps on low voltage harnesses with existing hardware applying one or two drops of item #1 Loctite
to the fastener threads.
42. Re-secure harness with item #7 TyRaps as required.
C/S View

Re-connect Charge Rail Heater
Wiring and Torque to 22 FT-LBS.
Apply Item #6 Anti-Corrosion
Compound

S/S View

Re-connect
DC Charge
Box Low
Voltage Wires
and Re-install
Clamps With
Existing
Hardware
Applying Item
#1 Loctite.

Re-connect Temp
Sensor Wiring
Item

Part Number

Description

1

081034

Loctite -243 Medium

6

8111767

Anti – Corrosion Compound NYK-77

7

5955945

TyRap – 14 IN Black

Figure 11C: Charge Rail Installation Location Reference.

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43. Re-connect the HV cable quick disconnects to the ESS unit. See Figure 12.
44. Close the side screen panels and re-install the existing hardware applying one or two drops of item #1 Loctite
to their threads and torque to 50 IN-LBS. Apply torque marks after torquing.
45. Re-install MSDs.

HV
POSITIVE

HV
NEGATIVE

Re-install Side Screens
apply Item #1 Loctite to
hardware threads and
Torque to 50 IN-LBS

Re-install MDS’s

Item
1

Part Number

Description

081034

Loctite -243 Medium

Figure 12: Upper ESS HV Cable Connection and Side Screen Location Reference.

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Section 3 – Rear ESS Assembly Removal.
46. Open the rear ESS access door and locate and remove the MSDs from each ESS unit and install a dust
cover. See Figure 13.
47. Open streetside and curbside upper side corner panels. Remove the gas springs supporting the ESS access
door on the bus side and raise the access door in the up position. Tyrap the door to the bracket inside the
streetside and curbside side upper corner panels.
48. Support the rear bumper with a forklift, remove the four retaining bolts, and remove the rear bumper and set
mounting hardware aside for re-installation. See Figure 13.
49. Remove the lower corner pillars (including turn signals and brake lights) and brackets and set mounting
hardware aside for re-installation. See Figure 13.
Remove Lower Corner Pillars

Remove Bumper

Remove MSDS

Figure 13: Lower Corner Pillars and Rear Door Removal Location Reference.

50. Disconnect HV cables from both ESS packs. Note: Positive and negative connections are color coed by color
when reconnecting. See Figure 14.
51. Secure HV cables out of the way for ESS removal.

Figure 14: HV Cable Connection Location References.

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52. From streetside rear corner, disconnect ESS grounding strap to bus frame. See Figure 15.

Disconnect Ground Strap & Set Hardware Aside
Figure 15: ESS Ground Strap to Bus Frame Location Reference.

53. From the curbside rear of the bus, place suitable coolant catch container under the ¼ turn drain vent valve on
the BTMS. Open the vent valve to drain the coolant out of the rear ESS packs. Open the vent valve on the
roof at the BTMS module. When the transfer pump starts pulling air through the system open the vent valves
at the front of the vehicle. Once completed draining close valves.
54. Remove the clear BTMS vent line from the ESS frame.
55. Disconnect and secure the low voltage harness connected to both ESS packs. Disconnect the supply and
return coolant lines from both ESS packs. See Figure 16A. Install coolant line caps on the ends of each fitting.
Remove BTMS Line

Remove LV
Connections and
Coolant Lines

Figure 16A: Low Voltage and Coolant Line Connections Location References.

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56. Remove the quick fill port drain hardlines and capture any lost coolant in a suitable container. Place quick fill
port mounting hardware aside for re-installation. See Figure 16B.
57. When lines are empty remove both hoses from the hard lines. Set clamps and hardware aside for reinstallation. See Figure 16B.

Remove Quick
Fill Port Lines

Remove Quick Port
and Clamps

Figure 16B: Low Voltage and Coolant Line Connections Location References.

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58. Remove the corner pillar bracket mounting hardware and set aside for re-installation. See Figure 17.
59. Remove the street side and curbside struts as follows: See Figure 17.
A.

Loosen the jam nut and remove the 1” upper nut on the strut.

B.

Remove the ¾” lock nut, bolt, and washers that attach the lower end of the strut to the main frame rail
bracket.

C.

Remove the strut itself.

60. Remove the pressure fill assembly mounting hardware and set aside for re-installation. See Figure 17.
Pressure
Fill
Remove
Struts

Corner Pillar Brackets and Hardware
Figure 17: Rear Struts and Side Structure Hardware Removal Location Reference.

61. Using big tyraps, secure both struts along with, HV cables, and AC drain hoses above the ESS packs. See
Figure 18.

Figure 18: Struts, HV cables and AC Drain Hose Securement Location References.

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62. Support the rear frame members with jack stands. See Figure 19.

Install Jack Stands
Figure 19: ESS Frame Member Jack Stand Location Reference.
63. Remove the hardware securing the ESS rack on the front and rear chassis. (2 sets each side) Set hardware
aside for re-installation. See Figure 20.
ESS Rack
Hardware

ESS Rack
Hardware

Figure 20: ESS Pack Assembly Mounting Hardware Location Reference.

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64. Support the ESS packs with forklift and remove ESS pack assemblies. See Figure 21.



NOTE: Before removal of the ESS, ensure no harnesses, cables, ground straps, or coolant hoses are
connected. Use a spotter to ensure the forks are captured within the pockets on the ESS frame and not
resting on the composite ESS enclosure. A c-clamp may be used to ensure the ESS frame does not slide
on the forks.

Figure 21: Rear ESS Pack Assembly Removal Location Reference.

65. Move the ESS battery packs to a clear and open workspace. Place block of wood under the ESS battery pack
assembly on each side and two in the middle for support. See Figure 22.
Wooden
Spacer
Blocks

Figure 22: ESS Battery Packs Wooden Block Under the Assembly Location Reference.

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Section 4: Rear ESS Enclosure Separation.
66. Remove fasteners securing the upper ESS packs to the frame (four fasteners on each side). Set hardware
aside for re-installation. See Figure 23.
67. Remove ground strap from ESS pack at ESS frame 2X locations and set hardware aside for re-installation.
See Figure 23

Upper
ESS Pack
Mtg Hdw.

Remove Frame
Ground Strap
at ESS

ESS2
(Top)

ESS1
(Bottom)

Figure 23: Upper ESS Frame Mounting Hardware Location Reference.

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68. Use a forklift with an appropriate hoist boom and straps (one in each corner for proper rigging), lift the upper
ESS pack (ESS2) from the frame assembly. See Figure 24.
69. Once ESS2 is removed from over top of ESS1 place on a suitable stand.
70. Connect an appropriate lifting device to the ESS unit being removed. See Figure 24.



NOTE: Lifting device securement straps should be connected at no less than 60 degrees as shown
below to prevent strap damage to the ESS enclosure or connected to a lifting device wider than the ESS
unit being removed in a vertical position as shown below to prevent strap damage to the ESS enclosure.

Figure 24: Rigging for Lifting Upper ESS Battery Pack Location Reference.

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71. Locate the serial number documentation form in Appendix A of this ITS or use the electronic version if
provided by your RPSM.
72. Locate the serial number plates on the side of each unit being removed and installed and fill out the form and
return to the RPSM for warranty and S/N tracking removed and installed units. See Figure 25.

ESS 2
Upper Rear

ESS 1 Rear
Bottom

Figure 25: Rear ESS Assembly Serial Number Documentation Location Reference.

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73. Inspect each ESS unit removed and to be installed for the correct ground cable securement. Ref ESS1 and
ESS2. See Figure 26.