SAV.1E.2012MA

SERVICE BULLETIN

BS4153ER1

REFERENCE:

Nova Bus Manuals

APPLICATION DEADLINE: 2019JL26

SECTION:

02: Doors and Mechanism

CLAIM REFERENCE NUMBER: WB-4153

RS NO:

MQR 7621-1165

EFFECTIVE IN PROD.:

N/A

SUBJECT:

Front door - Upper brush cover seal

JUSTIFICATION:

Automatic Passenger Counter may report erroneous data due to dust or water intrusion
on optical front door sensor lens.

LEVEL

DIRECT CHARGES

DESCRIPTION

1

Installation of rubber seal to cover the upper door brush with
the hardware provided.

2

–

TIME

LABOUR

MATERIAL

Nova Bus

Nova Bus

45 min

–

–

–

MATERIAL
PART NO

REV.

1

N91377

A

SEAL FRT OVRHD APC SENSOR PRCT

–

9

9415578

–

SCREW 10-24 X 3/4 TAP PAN CR

–

9

N8906932

–

WASHER

–

–

–

–

–

QTY

DESCRIPTION

REPLACES PART N°

LEVEL 1

LEVEL 2

–

Materials will be available within 21 days once your order has been placed. To order, please contact Prevost Parts by phone
at 1-800-771-6682, by fax at 1-888-668-2555 or by email at prevostparts.commandes@volvo.com. Specify document number,
quantity of parts required and shipping address.

DISPOSAL OF PARTS
REMOVED PARTS ARE:

DISCARDED *

RETAINED

Yes

–

* Dispose of the unused parts and the defective parts in
accordance with local environmental standards in effect.

REVISION HISTORY
REV.

DATE

NR

2018AL10

Initial release

R1

2018JN28

Replaced screw N20265 5/8" by 9415578 3/4" in length

APPROVED BY: Daniel Theriault

CHANGE DESCRIPTION

WRITTEN BY

Kumaraswamy K S

Digitally signed by Daniel Theriault
DN: cn=Daniel Theriault, o=Nova Bus, ou, email=daniel.theriault@volvo.com, c=CA
Date: 2018.06.29 08:12:45 -04'00'

Yuvaraj

PAGE 1 OF 7

SAV.1E.2012MA

SERVICE BULLETIN
ROAD NUMBER
CLIENT

ORDER

BS4153ER1

VIN (2NVY/4RKY...)

FROM

TO

FROM

TO

7300

7301

S92Y1D4500275

S92Y3D4500276

QTY

Démo US

L724

2

SEPTA - Pennsylvania

L728

-

-

L82W7D4500335

L82W7D4500335

1

SEPTA - Pennsylvania

L749

7302

7354

S92Y7D4500409

S92L2E4500470

53

SEPTA - Pennsylvania

L743

7356

7370

S92L1E4500489

S92L2E4500503

15

SEPTA - Pennsylvania

L741

7355

7355

S92L4E4500504

S92L4E4500504

1

SEPTA - Pennsylvania

L744

8601

8689

L82L7E4500570

L82LXE4500661

89

SEPTA - Pennsylvania

L742

7371

7414

S92L6E4500729

S92L7E4500772

44

SEPTA - Pennsylvania

L745

7415

7415

S92L0F4500873

S92L0F4500873

1

SEPTA - Pennsylvania

L746

7416

7454

S92L7F4500952

S92L8F4501012

39

SEPTA - Pennsylvania

L861

7300

7484

S92L5G9775188

S92L8G9775220

32

PAGE 2 OF 7

SAV.1E.2012MA

SERVICE BULLETIN

BS4153ER1

WARNING

Follow your internal safety procedures.

PROCEDURE
1.1.

Park the vehicle on an even surface with transmission in neutral (N).

1.2.

Open the front door.

1.3.

Set the Master control switch in the STOP position (see Figure 1).
Master control switch in
STOP position

Figure 1 - Master Control Switch in STOP Position

1.4.

Locate the upper door brush of the front door (see Figure 2).

Brush to be Retained in same
Position and only Hardware to be
Removed

Figure 2 - Typical Location of Upper Door Brush

PAGE 3 OF 7

SAV.1E.2012MA

SERVICE BULLETIN
1.5.

BS4153ER1

Remove the hardware holding the upper door brush and retain the brush in its original position.

NOTE

The rubber seal must be installed correctly. Its positioning is determined by the curve in the rubber seal.
The rubber seal must curve toward the door.
1.6.

Align the holes of rubber seal (N91377) with the pre-existing holes on the door structure (see Figure 3).

Interior of the Bus

Rubber Seal

Concave Side of the Rubber
Seal to be Fixed on the Bus
Structure
Convex Side of the Rubber
Seal to be Facing the Bus
Interior

Figure 3 - Alignment of Rubber Seal

PAGE 4 OF 7

SAV.1E.2012MA

SERVICE BULLETIN
1.7.

BS4153ER1

Secure the rubber seal and upper door brush with the new screws (N20265) and washers (N8906932) (see
Figure 4).

New Hardware Installed

Rubber Seal

Figure 4 - Installation of Rubber Seal

ADJUSTING THE UPPER BRUSH
1.8.

Adjust the upper door brush while loosening the screws from inside the vehicle.

1.9.

Position the brush so that it touches lightly the outside of the door, without straddling it.

1.10.

Check from outside the vehicle, with closed door panels, that the brush lightly touches the outside of the
door. If it does not touch, reposition the brush.

1.11.

Tighten the brush retaining screws.

1.12.

Place the Master control switch in ON position.

1.13.

Check for proper functioning of the front door.

PAGE 5 OF 7

SAV.1E.2012MA

SERVICE BULLETIN

BS4153ER1

ADJUSTING OVERHEAD SENSORS
1.13.1. UTA’s overhead diffuse sensor assembly (see Figure 5 and Figure 6), used on SEPTA Nova buses
is identical in function to the retroreflective sensor, but differs in operation. The overhead sensor
“strips” each contain a series of infrared emitter LED’s and a series of infrared receivers. When
emitted infrared light is detected, by reflecting back from an object (passenger) below, the output of
the sensor is triggered and a signal sent to the Smart Sensor.
The sensitivity of each sensor “strip” is adjustable by a small potentiometer which can be seen
and accessed through a small hole in the sensor lens. Turning the potentiometer clockwise with a
small straight-blade screwdriver will increase the detection range of the sensor. Turning the screw
counterclockwise will decrease the detection range.

Figure 5 - Typical View of Overhead Sensor Assembly

Any sensor mounted to the underside of the door header, near the outside of a bus is subject to
accumulation of water/dirt/air system oil, etc., which may penetrate the door seal or drip from the door
motor area above. UTA’s sensor assemblies are no exception to this, and cleaning of the sensors
may be required.
As with any optical situation (car windshield, eyeglasses, camera lenses, etc) this accumulation
of dirt or residue will restrict the light passing through the lens. In the case of APC infrared sensors,
accumulation of dirt will restrict the emitted infrared light AND the light returned from the reflection
from the passenger below. This has the same effect as “shortening” the detection range of the sensor
by the adjustment potentiometer.

Figure 6 - Typical Location of Overhead Sensor Assembly mounted over Novabus Doorway

PAGE 6 OF 7

SAV.1E.2012MA

SERVICE BULLETIN

BS4153ER1

SENSOR ADJUSTMENT
NOTE

ALWAYS CLEAN THE SENSORS PRIOR TO ATTEMPTING ADJUSTMENT - Detection range of dirty sensors
can be 10-12” less than clean sensors he rubber seal must be installed correctly. Its positioning is determined
by the curve in the rubber seal. The rubber seal must curve toward the door.
Detection range is measured from the FLOOR.
Always use a “standard” target when adjusting diffuse sensors – UTA recommends brown cardboard as it
is readily available and optically “neutral”. That is, has an “average” texture and color.
1.13.2. The detection range of the overhead sensors is adjustable to accommodate different mounting heights.
In the case of SEPTA’s Novabus fleet, the detection range should be set to:
Outboard Sensor – 30-32”
Inboard Sensor – 36-38”

NOTE

Overhead sensor adjustment can be an iterative process. The above measurements are given as a typical
starting point for adjustment.

Below is an illustration of the sensor adjustment/detection range (see Figure 7). Note the outboard
sensor is adjusted several inches lower than the inboard. This is to enhance the separation between
the detection point of the two sensors, and to aid in detecting passengers stepping up into the bus
from the ground (or down, when exiting).

Figure 7 - Typical View of the Sensor Adjustment/Detection Range

1.14.

The vehicle may be returned to service.

PAGE 7 OF 7