NHTSA ID Number: 10168950
Manufacturer Communication Number: SC-19-133
TSB/Document Date: 2019-12-07
Summary
This campaign updates the Grayson battery thermal management system to the latest version for improved performance.
ISSUE DATE:
SERVICE BULLETIN SUBJECT:
VINs or MODELS AFFECTED:
COMPLETE BY:
SERVICE BULLETIN #:
10-16-2019
Grayson Quality Campaign
Service Specified Catalyst Buses
Next Service Opportunity
SC-19-133
NOTICE! It is expected that this process will require 4 hours per bus. Please
schedule appropriately to minimize vehicle downtime.
GRAYSON QUALITY CAMPAIGN
Description
This campaign updates the Grayson units to the latest version for improved performance.
Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789
1|Page
Tools/Supplies Required
•
See OEM Instructions
Parts Required:
•
•
•
•
050169
050168
050167
050166
BRACKET - EWH, ROOFTOP BTMS, GRAYSON
TEMPERATURE SWITCH, ROOFTOP BTMS, GRAYSON
DOWTY SEAL, ROOFTOP BTMS, GRAYSON
BTMS THERMISTOR HARNESS, ROOFTOP BTMS, GRAYSON
Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789
1 EA
1 EA
1 EA
1 EA
2|Page
Procedure
1. Using the following OEM instructions, perform the Grayson Quality Campaign.
2. All Safety Procedures must be followed, including Lockout/Tagout and Safe Rooftop Access.
3. Unedited OEM instructions follow in their entirety.
Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789
3|Page
GRAYSON BATTERY THERMAL MANAGEMENT SYSTEM
PART NUMBER - HP-4456-450
Installation instructions for
Thermostat MP-1053-027 located in Grayson Thermal
Systems Electric Water Heater (EWH) HP-4781-100
Thermostat Part Number:
MP-1053-027
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
ISOLATION OF HIGH VOLTAGE
Prior to all work commencing
please ensure the Proterra LOTO
(Lock Out Tag Out) Scheme is
adhered to.
DATE: 21/03/2019
AUTHOR: A. Welch
Ensure you have the correct
training and authorisation to isolate
the bus with all of the correct
equipment.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
EWH Thermostat Installation
Thermostat Part Number:
MP-1053-027
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Remove Top Panels
NB: 19x M6
Bolts to be
removed
(Where shown)
CAUTION: Unit to be fully isolated prior to dis-assembly.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Remove the header tank cap by pressing
down and rotating anti-clockwise. Keep
the header cap in a safe place until
required to be refitted.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Drain the BTMS circuit of coolant as per
the vehicle manufactures guidelines.
The system only needs to be drained to a
level below the inlet and outlet pipes of
the unit
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Locate the heater end plate
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Remove Existing Plug
NB: Some
coolant may still
be inside the
heater unit.
CAUTION: Ensure the unit has been isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
NB: 5mm Hex
key to be used.
Insert Thermostat & Dowty Seal
NB:
Maximum
tightening
torque 16Nm
NB: Ensure thread
is clean on both
components
NB: Assemble
sensor and
dowty seal prior
to fitting to unit.
NB: Apply
Loctite 577 to
thread of sensor
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Unplug Electrical Harness
NB: Unplug the current
harness from both
electrical boxes.
Do not remove from unit
NB: 40-pin
Connector will
require a
4mm hex key.
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
De-pin 40-pin Connector
NB: Pins 9, &
32 to be
removed from
connector
9
32
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
De-pin 6-pin Connector
NB: Pins 1, &
5 to be
removed from
connector
1
5
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Insert New Pins (40-Pin Connector)
NB: Pin 9 to be
populated with
pin from the
new harness
9
32
NB: Pin 32 to be
populated with
a blank insert.
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Insert New Pins (6-pin Connector)
NB: Pins 1, & 5
to be
populated
with the new
harness.
1
5
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Tidy-up New Harness
NB: When modifications
are complete, the new
harness should be cable
tied to the original.
NB: 40-pin
Connector will
require a
4mm hex key.
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Re-plug Electrical Harness
NB: Plug the newly
modified harness into
both electrical boxes.
NB: 40-pin
Connector will
require a
4mm hex key.
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Connect harness to thermostat
NB: Plug the remaining
2-pin connector into the
thermostat
CAUTION: Ensure the unit has been fully isolated.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
When all parts are correctly installed refill the system with the
coolant removed at the start of the process. Operate the system
and ensure the coolant level is correct. If the coolant level is low
add additional coolant. Please confirm the coolant added to the
system is correct for the application. Refit the header tank cap.
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Re-install Top Panels
NB: M6 Bolt
tightening torque
11Nm (19 Places,
where originally
removed)
Driving the Future of Thermal Management
GFN 436 Issue 4 22.01.19
Standard
Operating
Procedure:
Safe Work
Instructions:
BTMS CONTROLLER REPROGRAMMING Operation Steps
Preparation for BTMS controller
reprogramming
1
On the left is presented
BTMS controller which
Is located in LV box
NOTE: PHOTOS INCLUDED ARE ONLY FOR REPRESENTATIVE
PURPOSES ONLY
Operation Name
Preparation
IF IN DOUBT ALWAYS ASK
Tools & Equipment Required
Personal Protective Equipment Required
Reason for Revision Date
Doc No.
Revision
Cycle Time
Originator
Approved
18/09/19
1
A
P Haluszczak
N Staunton
Standard
Operating
Procedure:
Safe Work
Instructions:
BTMS CONTROLLER REPROGRAMMING Operation Steps
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TSB/Document ID: SC-19-133
Replacement Service Bulletin Number:
MFR Communication Date: 2019-11-15
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ELECTRICAL SYSTEM
MFR Component System:
MFR Component Subsystem:
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