Content .. 97 98 99 100 ..

Loader Bobcat 773. Manual - part 99

–8–2–

773 BICS Loader

Service Manual

SYSTEMS ANALYSIS

Page

Number

BOBCAT OPERATION SENSING SYSTEM (BOSS

)

BOSS

DIAGNOSTIC TOOL

Procedure

8–21

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

BOSS

INSTRUMENT PANEL

Removal And Installation

8–27

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

MONITOR SERVICE CODES

Alphabetic Codes

8–22

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Numeric Codes

8–22

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Codes

8–23

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OPERATION SENSING SYSTEM UNIT

Removal And Installation

8–26

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RPM SENSOR

Adjustment

8–21

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SENDER AND SENSOR

Service Checks

8–28

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Component

8–28

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TROUBLESHOOTING THE BOSS

& L.C.D. DISPLAY

Chart

8–25

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Revised Jan. 99

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

)

(S/N 509648900 & Above) (S/N 509617300 & Above)

Inspecting The BICS

™

Controller

NOTE: Record what lights are blinking (if any) and

number of blinks. Refer to Page 8–4.

Inspecting The Seat Bar Sensor (Engine RUNNING)

Inspecting The Traction Lock (Engine RUNNING)

Inspecting The Lift Arm By–Pass Control

Inspecting Deactivation Of The Auxiliary Hydraulics

System (Engine STOPPED – Key ON)

1. Sit in the operator’s seat. Turn key ON, lower the

seat bar and disengage the parking brake pedal.

Press the green PRESS TO OPERATE Button. All

five BICS controller lights should be ON (Items 1,

2, 3, 4 & 5) [A].

2. Engage the parking brake pedal and raise the seat

bar fully. System Activated (Item 1), Seat Bar (Item

2), Valve (Item 3) and Traction lights (Item 4) [A]

should be OFF.

3. Exit the loader and press Traction Lock Override

button. Traction light (Item 4) [A] should be ON.

Press override button again and Traction light

(Item 4) [A] should be OFF.

4. Sit in the operator’s seat. Lower the Seat Bar.

Press the green PRESS TO OPERATE Button.

Press the auxiliary hydraulics switch. The auxiliary

switch light will come ON. Raise the Seat Bar. The

light should be OFF.

5. Sit in the operator’s seat. Lower the seat bar.

Engage the parking brake pedal. Fasten the seat

belt.

6. Start the engine and operate at low idle. Press the

green PRESS TO OPERATE Button. While

raising the lift arms, raise the Seat Bar fully. The lift

arms should stop. Repeat using the tilt function.

7. Fasten the seat belt, disengage the parking brake

pedal, press the green PRESS TO OPERATE

Button and raise the Seat Bar fully. Move the

steering levers slowly forward and backward. The

Traction lock should be engaged. Lower the Seat

Bar. Press the green PRESS TO OPERATE

Button.

8. Engage the parking brake pedal and move the

steering levers slowly forward and backward. The

Traction lock should be engaged.

9. Raise the lift arms 6 feet (2 meters) off the ground.

Stop the engine.

Turn the lift arm by–pass control knob clockwise

1/4 turn. Then pull up and hold the lift arm by–pass

control knob until the lift arms slowly lower.

Additional Inspection For Loaders With Advanced

Hand Controls

10. Sit in the operator’s seat and fasten the Seat Belt.

Lower the Seat Bar, start the engine and press the

green PRESS TO OPERATE Button.

11. Raise the lift arms about 6 feet (2 meters) off the

ground.

12. Turn the key OFF and wait for the engine to come

to a complete stop.

13. Turn the key ON. Press the green PRESS TO

OPERATE Button, move the left hand control

toward the operator. The lift arms should not lower.

14. Move the right hand control away from the

operator. The bucket (or attachment) should not tilt

forward.

Revised Jan. 99

(Engine STOPPED – Key ON)

P–10157

773 BICS Loader

–8–3–

Service Manual

The Bobcat Interlock Control System (BICS)
must deactivate the lift, tilt and traction drive
functions. If it does not, contact your dealer for
service. DO NOT modify the system.

W–2151–0394

AVOID INJURY OR DEATH

System

PRESS TO OPERATE

Lift, tilt and traction

System Activated circuit shorted to

Activated

button is activated button not activated functions will not

battery voltage.*

operate.

System Activated circuit shorted to
ground.

Seat Bar

Seat Bar Down.

Seat Bar Up.

Lift, tilt and traction

Seat bar sensor circuit shorted to

functions will not

battery voltage*.

operate.

Seat bar sensor circuit shorted to
ground.

Valve

Control Valve

Lift and tilt functions

Valve output circuit shorted to battery

Can Be Used.

Cannot Be Used.

will not operate.

voltage*.

Valve output circuit shorted to ground.

Valve output circuit is not grounded.

Traction

Loader can be

Loader cannot be

Traction lock hold coil circuit is open.

moved forward

moved forward and

Traction lock hold coil circuit shorted

& backward.

backward.

to battery voltage*.

Traction lock hold coil circuit shorted
to ground.

Traction lock pull coil circuit is open.

Traction lock pull coil circuit is shorted
to battery voltage*.

Traction lock pull coil circuit is shorted
to ground.

Power

BICS Controller

BICS Controller is

Lift, tilt and traction

is operating

not operating

functions will not

N/A

correctly.

operate.

Flashing Indicator Means System Problem

(See Your Bobcat Dealer for Service)

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

) (S/N 509648900 & Above) (S/N 509617300 & Above) (Cont’d)

Troubleshooting Chart

The following list shows the effects which can happen to the loader, and the probable causes when the BICS Controller
lights are off or flashing. Have the service procedure performed ONLY BY QUALIFIED BOBCAT SERVICE PERSONNEL.

Effect on Operation

of Loader

Indicator

When Light Is

Number of

Light

Light ON

Light OFF

OFF

Flashes

Cause

NOTES:

(1) If the System Activated and/or seat bar sensor circuits are open, the corresponding lights will be OFF. If

one of the lights stay OFF, check the circuit for continuity.

(2) If all five lights flash repeatedly, the voltage supply is greater than 16 volts or less than 9 volts.

(3) Flashing patterns will repeat every 3.25 seconds.

* Normal BICS operating voltage is less than the electrical system voltage. If voltage is more, the circuit is shorted

to system voltage.

Revised June 01

–8–4–

773 BICS Loader

Service Manual

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

)

(S/N 509648899 & Below) (S/N 509617299 & Below)

Inspecting The BICS

™

Controller

(Engine STOPPED – Key ON)

1. Sit in the operator’s seat. Turn key ON, lower the

seat bar and disengage the parking brake. All five
BICS Controller lights should be ON (Items 1, 2, 3,
4 & 5) [A].

2. Engage the parking brake, raise the seat bar fully.

Seat bar light (Item 2) [A], valve light (Item 3) [A]
and traction light (Item 4) [A] should be OFF.

3. Raise up slightly off the seat. Seat light (Item 1) [A]

should be OFF.

NOTE: Record what lights are blinking (if any) and

number of blinks. Refer to BICS
Troubleshooting Chart, Page 8–7.

4. Exit the loader and press traction lock override

button. Traction light (Item 4) [A] should be ON.
Press override button again and traction light (Item
4) [A] should be OFF.

Inspecting The Seat And Seat Bar Sensors
(Engine Running)

Inspecting The Traction Lock (Engine Running)

Inspecting The Lift Arm By–Pass Control

Early Models with or without mechanical Hand Controls

Raise the lift arms six feet (2 m) off the ground. Stop the
engine, pull and hold the by–pass control knob. Push the
toe of the left foot pedal or move the left hand control in
toward the operator (hand controls) and the lift arms
should lower slowly.

Later Models with or without machanical Hand Controls

Raise the lift arms six feet (2 m) off the ground. Stop the
engine. Turn the lift Arm By–Pass Control Knob clockwise
1/4 turn. Then pull up and hold the Lift Arm By–Pass
Control Knob until the lift arms slowly lower.

(Later Model Loaders Only) Inspecting Deactivation
Of The Auxiliary Hydraulics System
(Engine STOPPED – Key ON)

5. Sit in the operator’s seat. Lower the seat bar.

Press the auxiliary hydraulics auxiliary switch. The
auxiliary switch light will come ON. Raise the seat
bar. The light should be OFF.

6. Sit in the operator’s seat, lower the seat bar and

engage the parking brake. Fasten the seat belt.

7. Start the engine and operate at low idle. While

raising the lift arms, raise the seat bar fully. The lift
arms should stop. Repeat using the tilt function.

8. Fasten the seat belt, disengage the parking brake,

and raise the seat bar fully. Move the steering
levers slowly forward and backward. The traction
lock should be engaged. Lower the seat bar.

9. Engage the parking brake pedal and move the

steering levers slowly forward and backward. The
traction lock should be engaged.

Revised June 01

P–03760

773 BICS Loader

–8–5–

Service Manual

Content .. 97 98 99 100 ..