SP18-39D

SP18-39D
Special Bulletin
Date
11.2018
Revision: D
Procedure updated. Additional tools depicted
Expiration
Release
Page
6
1(45)
03/22/2022
SCR CONVERTER REPLACEMENT - AFTERTREATMENT SYSTEM
Prevost vehicles & B13R (9700 us/can)
Table of contents
DESCRIPTION .............................................................................................................................................. 2
MODEL YEAR(S) and VEHICLES involved .................................................................................................. 2
MATERIAL NEEDED ..................................................................................................................................... 3
SPECIAL EQUIPMENT REQUIRED ............................................................................................................. 4
SAFETY PRECAUTIONS.............................................................................................................................. 6
Part 1- H3 SERIES AND X3 SERIES VEHICLES ......................................................................................... 7
PROCEDURE ............................................................................................................................................ 7
PRELIMINARY STEPS .......................................................................................................................... 7
SCR CONVERTER REMOVAL ............................................................................................................. 9
TAKE THE STRAPS AND BRACKETS APART FROM THE DEFECTIVE SCR CONVERTER ........ 18
INSTALL THE PRE-SCR NOx SENSOR ............................................................................................. 25
REINSTALL THE SCR CONVERTER IN ITS COMPARTMENT......................................................... 25
REINSTALL THE EXHAUST PIPE AND INSULATING BLANKET ..................................................... 29
INSTALLATION OF THE PM SENSOR ............................................................................................... 30
INSTALL THE POST-SCR NOx SENSOR .......................................................................................... 34
REINSTALL THE SCR CONVERTER DRAIN TUBE .......................................................................... 35
REINSTALLING THE “L” SHAPE BRACKET ...................................................................................... 35
DIFFUSER ASSEMBLY AND GRILLE INSTALLATION...................................................................... 36
FINAL STEPS ...................................................................................................................................... 40
PACKAGING FOR RETURN ............................................................................................................... 41
Part 2- VOLVO 9700 VEHICLES ................................................................................................................ 42
PROCEDURE .......................................................................................................................................... 42
FINAL STEPS ...................................................................................................................................... 42
PACKAGING FOR RETURN ............................................................................................................... 44
PARTS / WASTE DISPOSAL ...................................................................................................................... 45
Writer: EL

SP18-39D
Special Bulletin
Date
Expiration
11.2018
DESCRIPTION
Release
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2(45)
This special bulletin is the continuity of Special Bulletin SP18-35. Only if authorized, perform the
replacement of the SCR converter.
MODEL YEAR(S) and VEHICLES involved
NOTICE TO SERVICE CENTERS
Verify vehicle eligibility by checking warranty bulletin status with SAP or via ONLINE WARRANTY
SYSTEM available on Service / Warranty tab of Prevost's website.
Specific GHG17 & OBD18 compliant vehicles
This bulletin does not necessarily apply to all the above-mentioned vehicles, some vehicles may have been modified
before delivery.
Writer: EL

SP18-39D
Special Bulletin
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11.2018
Expiration
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MATERIAL NEEDED
Order kit SP18-39 which includes the following parts:
Part No.
Description
Qty
500952
SCREW, TAPPING BDG PH SS #8X1/2
12
504637
CABLE TIE, NYLON BLK
12
540067
EXHAUST CLAMP 5"
1
21021850
CLAMP, V-BAND 5-INCH
2
21095726
GASKET EXHAUST PIPE V-BAND JOINT, 5-INCH
2
22303390
NOx SENSOR, PRE
1
22303391
NOx SENSOR, POST
1
22998036
TIE, STAINLESS STEEL
4
23190006
SCR CONVERTER
1
NOTE
Material can be obtained through regular channels.
Writer: EL

SP18-39D
Special Bulletin
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11.2018
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SPECIAL EQUIPMENT REQUIRED
scissor lift – mobile platform
electric winch
swivel hook for fork lift
Vestil LM-HP6-S Swivel Lift
Master Hook Plate, 24" Width,
6” Height, 6000 lbs Capacity
Oberg tilt lift 2,000 lbs. Capacity – special lifting tool available
in Service Centers
use with half-inch ratchet or half-inch breaker bar
Writer: EL

SP18-39D
Special Bulletin
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11.2018
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fork lift truck
JCHL Soft Loop Tie Down
SPECIAL LIFTING EQUIPMENT ARRANGEMENT
Writer: EL

SP18-39D
Special Bulletin
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11.2018
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SAFETY PRECAUTIONS
•
Eye protection should always be worn when working in a shop.
•
Rules for Personal Protection Equipment should always be respected. Wear your PPE
including but not limited to the following:
Safety
First!
Writer: EL

SP18-39D
Special Bulletin
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Expiration
11.2018
Release
Page
6
7(45)
Part 1- H3 SERIES AND X3 SERIES VEHICLES
PROCEDURE
DANGER
Park vehicle safely, apply parking brake, stop the engine. Prior to working on the vehicle, set the ignition
switch to the OFF position and trip the main circuit breakers equipped with a trip button. On the Commuter
type vehicles, set the battery master switch (master cut-out) to the OFF position.
Lockout & Tag out (LOTO) must be performed during set-up, maintenance or repair activities. Refer to
your local procedure for detailed information regarding the control of hazardous energy.
PRELIMINARY STEPS
1. Open the engine compartment door and the SCR converter access door.
2. Remove the SCR converter access door. Doing so
will allow extraction of the SCR converter out of its
compartment.
3. The SCR converter is heavy, huge and the free space in the opening is limited. Do whatever
is necessary to protect the fiberglass and the paint around the opening giving access to the
SCR. Using adhesive tape, place pieces of cardboard around the area.
Writer: EL

SP18-39D
Special Bulletin
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Expiration
11.2018
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4. Remove the SCR overhead ventilation grille.
5. Loosen the clamp and then remove the diffuser
assembly with the drain tube attached.
6. Support the exhaust pipe between the SCR and the
flexible section. Remove the insulating blanket
around the pipe and then remove the two V-band
clamps securing the exhaust pipe. Move the exhaust
pipe to clear it from the SCR converter compartment.
H3 SERIES
X3 SERIES
Writer: EL

SP18-39D
Special Bulletin
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SCR CONVERTER REMOVAL
7. Disconnect the SCR converter drain tube
H3 SERIES
X3 SERIES
Writer: EL

SP18-39D
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8. Unscrew and remove the NOx sensor and module.
Return the NOx sensor with the defective SCR
converter to Prevost.
H3 SERIES
X3 SERIES
Writer: EL

SP18-39D
Special Bulletin
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Expiration
11.2018
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9. Unscrew the PM (particulate matter) sensor from the
SCR converter.
10. Secure the PM sensor and harness next to the PM
sensor module on the panel.
Handle the PM sensor with care as it has fragile
ceramic part that can be damaged by a slight
impact
Save the PM sensor for reuse
H3 SERIES
PM SENSOR
X3 SERIES
11. H3 SERIES - Remove the module panel and put
aside.
H3 SERIES
Writer: EL

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12. X3 SERIES - Remove the module panel and put
aside.
X3 SERIES
13. Install special lifting equipment (see SPECIAL
EQUIPMENT REQUIRED) to the lifting eyelets of
the SCR converter.
See the image on the right and refer to SPECIAL
EQUIPMENT REQUIRED
14. With the lifting equipment, support the weight of the
SCR converter.
Writer: EL

SP18-39D
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15. H3 SERIES - Remove the upper mounting bracket.
Unscrew and remove six bolts identified on the
image.
H3 SERIES
16. X3 SERIES - Remove the upper mounting bracket.
Unscrew and remove seven bolts identified on the
image.
X3 SERIES
17. H3 SERIES - Thread the upper bolt out about 1/4″.
18. H3 SERIES - Remove the lower bolt.
H3 SERIES - BOLTS SECURING THE SCR
CONVERTER TO THE CHASSIS - STREET SIDE
Writer: EL

SP18-39D
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19. H3 SERIES - Thread the upper bolt out about 1/4 in.
20. H3 SERIES - Remove the lower bolt.
H3 SERIES - BOLTS SECURING THE SCR
CONVERTER TO THE CHASSIS - CURB SIDE
21. H3 SERIES - Using the lifting device, lift the SCR converter a few inches so it will disengage
from the fixing points at the bottom.
22. X3 SERIES – Unbolt the lower support bracket from
the chassis (4 bolts).
X3 SERIES
Writer: EL

SP18-39D
Special Bulletin
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23. X3 SERIES – Lift the SCR converter and then
remove the lower support bracket to ease removal
of the SCR converter.
X3 SERIES
24. While proceeding with great care, take the SCR
converter out of the compartment through the L.H.
side opening. The SCR converter is heavy. Proceed
with the help of a co-worker.
CAUTION
RISK OF INJURY
Make sure the electric winch cannot be activated
inadvertently. The person who extracts the SCR
should not be in possession of the remote control.
CAUTION
RISK OF INJURY
The SCR lifting eyes can have very sharp edges.
Be sure to use the JCHL soft loop tie downs when
lifting and tilting the lower part of the SCR out of
the compartment.
Use the JCHL soft loop lifting straps to
pull the SCR from the compartment
Once the bottom of SCR is lifted high enough to clear
the opening, unhook the farmost lifting eye, this will
Writer: EL

SP18-39D
Special Bulletin
Date
11.2018
allow the outside bottom of the SCR to tilt out of the
opening. Please note that the Oberg lifting tool should
be locked in place.
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25. To extract the SCR from the compartment, tilt the
SCR clockwise 20° to increase clearance for the
NOx sensor mounting point.
Writer: EL

SP18-39D
Special Bulletin
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11.2018
Expiration
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26. Once secured on the work platform, reattach the lift
hoist and safely lift the SCR to the ground.
Writer: EL

SP18-39D
Special Bulletin
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18(45)
11.2018
TAKE THE STRAPS AND BRACKETS APART FROM THE DEFECTIVE SCR CONVERTER
It is IMPORTANT to take all the necessary
precautions in order to ease the installation
of the straps and brackets on the
replacement SCR converter. It is very
important to position the straps and the
mounting brackets as much as possible like
they were positioned on the defective SCR
converter. Doing so will greatly facilitate the
installation of the SCT in the compartment.
It is highly recommended to measure and/or
mark the position of the straps on the
defective SCR converter in order to have
references for positioning the straps on the
new installation.
ON THE STRAP, DRAW A LINE CENTERED WITH THE DRAIN
FITTING. MEASURE THE UPPER STRAP POSITION IN
RELATION TO THE EMBOSS
ON THE STRAP, DRAW A LINE CENTERED WITH CIRCULAR
EMBOSS. MEASURE THE LOWER STRAP POSITION IN
RELATION TO THE EMBOSS
Writer: EL

SP18-39D
Special Bulletin
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11.2018
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27. Remove the mounting straps and brackets
from the SCR converter. Unscrew the bolts
identified by the arrows.
wear cut resistant protection gloves when
removing mounting straps
H3 SERIES - UNSCREW THE BOLTS INDICATED BY THE
ARROWS
X3 SERIES - UNSCREW THE BOLTS INDICATED BY THE
ARROWS
Writer: EL

SP18-39D
Special Bulletin
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11.2018
Expiration
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28. H3 SERIES - Take the R.H. side lower bracket
apart from the SCR converter.
H3 SERIES - UNSCREW THE TWO BOLTS INDICATED
BY THE ARROWS
H3 SERIES - UNSCREW THE TWO BOLTS INDICATED
BY THE ARROWS
29. X3 SERIES - Install the insulating blankets recovered from the defective SCR converter.
Secure with stainless steel ties.
IMPORTANT: Make sure that the « V » clearance and the round clearance of the insulation
blanket are placed at the drain fitting and the stud found on the SCR converter respectively.
Writer: EL

SP18-39D
Special Bulletin
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Expiration
11.2018
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21(45)
30. Install the straps and brackets on the new SCR
converter.
Install the brackets exactly as on the defective
SCR
(H3 Series shown)
Writer: EL

SP18-39D
Special Bulletin
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11.2018
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31. Tighten the bolts just enough to hold the
straps in place while allowing movement for
position adjustment.
Caution : The bolt head must go into the
chamfered hole
BOLT WITH THE HEAD ON THE PROPER SIDE
(OPPOSITE SIDE OF THE DRAIN TUBE FITTING)
32. Adjust the straps position in reference to the
emboss.
Writer: EL

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11.2018
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33. H3 SERIES - Prior final tightening, make sure
that each strap is properly centered on its
respective bracket.
34. Once properly positioned, apply final torque
to the strap bolts.
FINAL TORQUE: 30-37 lbf-ft
Writer: EL

SP18-39D
Special Bulletin
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11.2018
Expiration
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35. H3 SERIES - Install the R.H. side lower
bracket and tighten the bolts (4x) to proper
torque.
FINAL TORQUE: 48 lbf-ft
H3 SERIES
Writer: EL

SP18-39D
Special Bulletin
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Expiration
11.2018
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INSTALL THE PRE-SCR NOx SENSOR
36. Apply anti-seize compound on the NOx
sensor threads and then fix onto the DPF
outlet. Secure the harness using nylon
ties.
NOx sensor torque: 37 lbf-ft
Return the old NOx sensor with the SCR
converter to Prevost
REINSTALL THE SCR CONVERTER IN ITS COMPARTMENT
37. H3 SERIES - Make sure that there is a 1/2″
gap between the washer pressed against
the bolt head and the bracket surface as
shown on the image at right (2 bolts).
H3 SERIES - LOWER BRACKETS
38. While proceeding with great care, insert the SCR converter in the compartment through the
opening using the lifting equipment. Use the same process as when performing the extraction
of the SCR. The SCR converter is heavy. Proceed with the help of a co-worker. DO NOT place
the SCR converter in final position yet.
Writer: EL

SP18-39D
Special Bulletin
Date
11.2018
39.
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H3 SERIES - Install the upper and lower
insulating blankets recovered from the
defective SCR converter. Secure with
stainless steel ties.
IMPORTANT: Make sure that the « V »
clearance and the round clearance of the
insulation blanket are placed at the drain
fitting and the stud found on the SCR
converter respectively.
Writer: EL

SP18-39D
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11.2018
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40. H3 SERIES - Install the SCR
converter in final position. Rest the
SCR converter at the fixing points
on the chassis with the two upper
bolts secured to both lower
brackets.
41. H3 SERIES - Tighten the two bolts
to a firm feel.
H3 SERIES
42. H3 SERIES - Thread in and tighten
the two lower bolts to a firm feel.
H3 SERIES
Writer: EL

SP18-39D
Special Bulletin
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11.2018
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43. X3 SERIES – Reinstall the lower support
bracket on the SCR converter.
44. X3 SERIES – Fasten the lower support to the
vehicle chassis.
X3 SERIES
Writer: EL

SP18-39D
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REINSTALL THE EXHAUST PIPE AND INSULATING BLANKET
45. Clean the sealing surfaces between the after-
treatment SCR converter inlet, the exhaust pipe and
the flexible section.
46. Using a new gasket, position the pipe to the after-
treatment SCR converter and install a new V-band
clamp. Tighten the V-band clamp to specification.
Proceed similarly with the other end of the exhaust
pipe.
Gasket, qty: 2
H3 SERIES
V-band clamp, qty: 2 (torque=100 lbf-in)
X3 SERIES
Writer: EL

SP18-39D
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47. Reinstall the insulating blanket.
H3 SERIES
X3 SERIES
X3 SERIES
INSTALLATION OF THE PM SENSOR
48. Recover the two harness mounts on the defective
SCR converter and install them on the replacement
SCR converter.
Writer: EL

SP18-39D
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49. H3 SERIES – Reinstall the sensor module panel.
H3 SERIES
50. Installation of the PM sensor. Before installing
the PM Sensor, shake the sensor close to your ear
to detect a broken ceramic noise. If there is a
sound of broken ceramic, reject the PM Sensor, it
is defective. Install a PM sensor in good condition.
51. Before connecting the PM Sensor,
make sure you align the keying tab
with the orientation slot in the mating
boss.

Writer: EL

SP18-39D
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52. Install the PM sensor and secure the harness as
shown using nylon ties.
PM sensor torque: 37 lbf-ft
PM sensor module: 89 lbf-in
H3 SERIES
X3 SERIES
X3 SERIES
Writer: EL

SP18-39D
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53. H3 SERIES – Take up the extra length of the PM
sensor harness shown on the image and secure to
a nylon tie mount.
H3 SERIES
Writer: EL

SP18-39D
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11.2018
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INSTALL THE POST-SCR NOx SENSOR
54. Apply anti-seize compound on the NOx sensor
threads and then fix onto the SCR converter. Secure
the harness as shown using nylon ties.
NOx sensor torque: 37 lbf-ft
H3 SERIES
X3 SERIES
Writer: EL

SP18-39D
Special Bulletin
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Expiration
11.2018
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35(45)
REINSTALL THE SCR CONVERTER DRAIN TUBE
55. Insert the tube into the fitting and then tighten firmly.
H3 SERIES
X3 SERIES
REINSTALLING THE “L” SHAPE BRACKET
56. H3 SERIES – Reinstall the upper mounting
bracket.
Writer: EL

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11.2018
DIFFUSER ASSEMBLY AND GRILLE INSTALLATION
57. Slide the diffuser assembly on the SCR converter
tube. Do not tighten at this moment.
H3 SERIES – NUT ON THIS SIDE
X3 SERIES – NUT ON THIS SIDE
Writer: EL

SP18-39D
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58. Install the drain tube.
59. Insert the drain tube in the drain tube guide.
H3 SERIES
X3 SERIES
Writer: EL

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60. Install the SCR converter compartment grille on the
top of the coach. Tighten the screw in the order
shown on the image.
#500952 tapping screw #8x1/2 SS
H3 SERIES
X3 SERIES
61. Adjust the spacing between the diffuser assembly
and the grille. The minimum spacing should be ¼″
(6 mm).
62. Adjust the diffuser assembly height above the grille.
The edge height should be 1/8″ to 1/4″ (3 mm to 6
mm) at the diffuser corner shown on the image while
the edge height should be 1/8″ to 1/2″ (3 mm to 12
mm) at the outer edge for the rest of the periphery.
Writer: EL

SP18-39D
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63. Slide the diffuser clamp close to the top of the SCR
converter outlet tube.
Measurement: between 1/8″ to 1/2″ (2 mm to 12
mm)
64. Tighten the clamp.
65. Reinstall the SCR converter compartment access
hatch.
Writer: EL

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11.2018
FINAL STEPS
66. Reconnect all previously removed cables to the negative (ground) battery terminals if
applicable.
67. Start the engine and check for leaks of the exhaust system and proper operation.
68. Check for diagnostic troubleshooting code related to the after-treatment system, in
particular, the PM sensor and NOx sensor.
69. Using TechTool, perform a Data Reset of the components that were replaced (refer to the
two following images).
Writer: EL

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70. Disregard the dialog box that requests DPF regeneration. Do not perform the regeneration.
PACKAGING FOR RETURN
71. Indicate serial number of new SCR converter and removed SCR converter on RO.
72. Return the old SCR converter using the packaging of the new unit.
If not possible, ideally use cardboard box where SCR converter is covered, capped
(reuse caps) and protected from elements and damage during shipping.
Tag part with RO and VIN info.
Writer: EL

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11.2018
Part 2- VOLVO 9700 VEHICLES
PROCEDURE
DANGER
Park vehicle safely, apply parking brake, stop the engine. Prior to working on the vehicle, set
the ignition switch to the OFF position and trip the main circuit breakers equipped with a trip
button. On the Commuter type vehicles, set the battery master switch (master cut-out) to the
OFF position.
Lockout & Tag out (LOTO) must be performed during set-up, maintenance or repair activities.
Refer to your local procedure for detailed information regarding the control of hazardous
energy.
You will find in Part 1 of this bulletin, useful information such as the diffuser removal/installation
procedure, strap installation, SCR converter insulating blanket installations, NOx sensor
installation, among others.
In complement to Part 1, please refer to the document listed below, available on Impact.
IDENTITY
ID/OPERATION
TITLE
129601506
2586-03-02-01
Aftertreatment Selective Catalytic Reduction (SCR) Catalyst, Replacement
FINAL STEPS
1. Reconnect all previously removed cables to the negative (ground) battery terminals if
applicable.
2. Start the engine and check for leaks of the exhaust system and proper operation.
3. Check for diagnostic troubleshooting code related to the after-treatment system, in
particular, the PM sensor and NOx sensor.
4. Using TechTool, perform a Data Reset of the components that were replaced (refer to the
two following images).
Writer: EL

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5. Disregard the dialog box that requests DPF regeneration. Do not perform the
regeneration.
Writer: EL

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PACKAGING FOR RETURN
6. Indicate serial number of new SCR converter and removed SCR converter on RO.
7. Return the old SCR converter using the packaging of the new unit.
If not possible, ideally a cardboard box where SCR converter is covered, capped (reuse caps)
and protected from elements.
Tag part with RO and VIN info.
Writer: EL

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45(45)
PARTS / WASTE DISPOSAL
Return the defective SCR converter to Prevost.
ESTIMATED TIME
The time required to perform this special bulletin is approximately:
Prevost vehicles
10 hours
Volvo 9700
3 hours
OTHER
VBC Bulletin
N/A
Fail Code
04.04-1
Defect Code
09
Syst. Count
B
Causal Part
21970125
Access all our Service Bulletins on
http://techpub.prevostcar.com/en/
or scan the QR-Code with your smart phone.
Prevost engages in a continuous program of testing and evaluating to provide the best possible product. Prevost, however, is not
committed to, or liable for updating existing products.
Writer: EL