ISSUE DATE:
SERVICE BULLETIN SUBJECT:
VINs or MODELS AFFECTED:
COMPLETE BY:
SERVICE BULLETIN #:
Labor Operation Code:

11-16-2020
Rear Door Aux Heat Tube Retrofit
Service Specified Buses
Next Service Opportunity
SC-20-162
VD41Z

NOTICE! It is expected that this process will require 14 hours per bus. Please
schedule appropriately to minimize vehicle downtime.

REAR DOOR AUX HEAT RETROFIT
Retrofit Description:

This procedure updates the rear door aux heat to stainless steel material for improved corrosion
resistance.

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

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Tools/Parts Required
Tools and Supplies Required:
1. 316-Inch Allen Socket
2. T-20 Torx Socket
3. T-30 Torx Socket
4. T-55 Torx Socket
5. 13mm Socket
6. 8mm Socket
7. Ratchet
8. Flat Blade Screwdriver
9. Calibrated Torque Wrench
10. Heat Gun
11. Putty Knife
12. Acetone
13. Alcohol
14. Shop Towels
15. Yellow Stanchion Paint RAL 1023

Kit Parts Required:
•

055828
RETROFIT KIT, AUX HEAT REAR DOOR TUBE ASSEMBLY (Consisting of)
• 122-9285
TUBE, EXIT DOOR, AUX HEAT
1 EA
• 018362
PLEXUS, MA-530
2 EA
• 043090
FITTING, DRAIN, 1/4"-18 MNPT
1 EA
• 009314
SEALER,CAULK, ALTROMASTIC, ZEAL/MIN/FUSION
2 EA
• 044137
CLAMP, CONSTANT TENSION, 21 to 38mm OD HOSE
4 EA
• 051571
BONDO, 1 QT, GLASS REINFORCED FILLER
2 EA
• 012138
CABLE TIE, HEAVY DUTY .5WIDE 9.1" BLACK
6 EA
• 017244
SPRING CLAMP, 1.00" ID HOSE
4 EA

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

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Procedure:
1. Complete the Proterra approved Lockout/Tagout procedure to make the bus safe for work.
2. Using a 3/16-Inch Allen Driver, remove the Hadley Panel above the exit door.

3. Using a T-30 Torx Driver, remove the Rear Door Closeout Panel shown highlighted in the
following illustration.

4. Disconnect the harness for the sensitive edge. Remove Cable Ties as necessary.

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

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5. Using a T-55 Torx Driver, remove the M12 Torx Screws at the top of each door leaf.

6. Remove each Door Leaf from the door frame by lifting them off the lower bearing as shown in
the following illustration.

7. Using an M8 Ratchet/Socket, remove the turnbuckle bolts at the top of each door leaf.

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

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8. Using an M8 Ratchet/Socket, loosen the hinge brackets at the bottom of the doorway.
Remove the door shafts from the upper and lower ball joints.

9. Using a 13mm Ratchet/Socket, remove the hinge brackets from the bottom of the doorway.

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

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10. Using a T-20 Torx Driver, remove the metal covers on each side or the rear doorway.

11. Using Pinch Clamp Pliers, clamp the coolant tubes in the location shown below. Remove the
spring clamps and Tee Fitting as shown.

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

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12. Using Pinch Clamp Pliers, clamp the coolant tubes in the location shown below. Remove the
Cable Ties and Spring Clamps. Detach the rear passthrough tube assembly from the 90degree tubes.

13. Using a Flat Blade Screwdriver, remove the M6 Screws shown circled in red below.
Disconnect the heated mat harness. Remove any caulk around the mat. Remove the mat.

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

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14. Using a Heat Gun, weaken the Bondo on top of the Tube Assembly. Using a Putty Knife,
remove the Bondo to access the Plexus adhesive on the Tube Assembly.
15. Using a Heat Gun and Putty Knife, de-bond the Plexus Adhesive that secures the Tube
Assembly to the bus body.
16. Remove the Tube Assembly from the Bus.
17. Using a Heat Gun and Putty Knife, remove any excess Plexus and/or Bondo from the area
where the Tube Assembly was removed.
18. Using 36-Grit Sandpaper, scuff the bus body for bonding to the new Tube Assembly (1229226).
19. Using a Power Drill with a 36-Grit Sanding Disk, scuff the areas shown outside the blue lines
on the new Tube Assembly (122-9285)

20. Using Alcohol and Shop Towels, clean the scuffed areas on the bus body and the Tube
Assembly (122-9285).
21. Using a Shop Towel, apply Plexus Primer to the scuffed areas on the new Tube Assembly
(122-9285).
22. Using a Plexus Gun, apply Plexus to the scuffed area on the new Tube Assembly (122-9285).
23. Lower the new Tube Assembly (122-9285) into position on the bus.

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

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24. Using a Plexus Gun, apply a bead of Plexus around the perimeter of the new Tube Assembly
(122-9285) to seal its edges.
25. Allow time for the Plexus to cure.
26. Using Pinch Clamp Pliers, connect the 90 degree silicone tubes at the rear to the new Tube
Assembly (122-9285).

27. Using Cable Ties (012138), secure the tubes to the mounting hardware.
28. Using an XX-Inch Combination Wrench, install the new Drain Fitting (043090) into the new
Tube Assembly (122-9285) as shown in the following illustration.

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

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29. Secure the new Tube Assembly (122-9285) to the reducer coolant tubes using Constant
Tension Worm Clamps (044137).
30. Using a Putty Knife, apply Bondo above the Tube Assembly (122-9285) to create a flat
surface for the heated mat. The Bondo may cover the entire passthrough plate as well as the
surrounding floor.
Note: Keep the Bondo out of the threaded inserts.
31. Reinstall the Heated Map.
32. Using a Caulking Gun, apply Caulk (009314) to the edges of the heated mat.
Heat Seam

33. Using a T-20 Torx Driver, reinstall the metal covers that were removed earlier.

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

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34. Using a 13mm Ratchet/Socket, reinstall the hinge brackets at the bottom of the doorway. Do
not tighten the bolts completely.

35. Reinstall the Door Shafts. Position the shafts over the bottom ball joint and guide them into
place.

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

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36. Using a 13mm Ratchet/Socket, tighten the M8 bolts on the bottom hinge brackets so that the
door leaves can be installed.
37. Using an M8 Ratchet/Socket, reinstall each turnbuckle bolt.

38. Lift each door leaf so that the bottom slot is over the lower bearing. Align the upper face of the
door with the door support. Using aT-55 Torx Socker, install the M12 Countersunk screws.

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

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39. Reconnect the sensitive edge harness. Use Cable Ties (012138) to secure the cables so that
they do not interfere with the motion of the doors.
40. Adjust the doors as necessary using the following illustrations.
a. A Adjust for forward and aft direction.
b. B Adjust for door clearance (Cross-car with body direction).
c. C Adjust the tightness of the doors.

41. Adjust the Turnbuckle for the bottom leaf position.
42. Using a 13mm Socket, and a Calibrated Torque Wrench, torque the M8 Bolts on the hinge
brackets to 22 foot pounds.
43. Using a T-55 Torx Socket and a Calibrated Torque Wrench, torque the M12 Countersunk
screws to 41 foot pounds.

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

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44. Using a 13mm Crow Foot Socket, and a Calibrated Torque Wrench, torque the turnbuckle
jamb nuts to 10 foot pounds.

45. Using a Tubing Cutter, remove 1-Inch of the Stanchion shown in the following illustration.

46. Using a Deburr Tool, smooth the edge of the modified Stanchion.
47. Paint the cut end of the Stanchion using Yellow Stanchion Paint RAL 1023.

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

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48. Using an Approved Safety Knife, modify the modesty panel as shown in the following
illustration.

49. Reassemble the Modesty Panel and Stanchion. The modified Modesty panel is shown in the
following illustration.

50. Using Alcohol and Shop Towels, clean up any dust and debris.
51. Remove the Lockout/Tagout devices and power on the bus.
52. Verify proper operation of the exit door before returning the bus to service.
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

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