Loader Bobcat 773. Manual - part 100

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

)

(S/N 509648899 & Below) (S/N 509617299 &
Below)(Cont’d)

Maintenance

Clean any debris, dirt or objects from under or behind the
operator seat [A] & [B]. The rear of the seat must move
up and down.

Inspect both Seat Rail Covers [B] for wear or damage.
Replace if necessary.

Clearance is necessary under the seat spring (Item 1) [B]
and the seat, to allow the seat to move up and down freely.
With adequate clearance, the seat sensor will be allowed
to function properly.

Inspect seat bar pivot area for tightness of linkage bolts.

Replace parts that are damaged. Use only genuine
Melroe replacement parts.

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

Revised June 01

A

P–03763

Clean area behind

and under seat.

–8–6–

773 BICS Loader

Service Manual

B

MC–02043

Operator

Seat

Seat

Spring

1

Seat

Sensor

Seat Rail

Cover

Seat

Operator in Seat

No Operator in Seat

Lift and tilt functions
will not operate.

Seat Bar

Seat Bar Down

Seat Bar Up

Lift, tilt and traction

2

Seat   bar  sensor  circuit  shorted  to

functions will not

battery voltage*.

operate.

3

Seat   bar  sensor  circuit  shorted  to
ground.

Valve

Control Valve Can Control Valve

Lift and tilt functions

1

Valve output circuit is open.

Be Used

Cannot Be Used

will not operate.

2

Valve output circuit shorted to battery
voltage*.

3

Valve output circuit shorted to ground.

3

Valve output circuit is not grounded.

Traction

Loader can be

Loader cannot be

Loader cannot be

1

Traction lock hold coil circuit is open.

moved forward &

moved forward and

moved forward and

2

Traction  lock hold coil circuit shorted

backward.

backward.

backward.

to battery voltage*.

3

Traction  lock hold coil circuit shorted
to ground.

4

Traction lock pull coil circuit is open.

5

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

6

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

correctly.

correctly.

operate.

2

Seat sensor circuit shorted to battery
voltage*.

3

Seat sensor circuit shorted to ground

Flashing Indicator Means System Problem

(See Your Bobcat Dealer for Service)

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

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

(4) If seat indicator light does not go ON, check for debris, dirt or objects under or behind the seat.

NOTE: On some early models with BICS controller S/N 200,000 and Above only, If the Seat Bar is lowered before

the seat sensor is activated, a 10 second delay will occur before the valve and traction lights come on.

* 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

773 BICS Loader

–8–7–

Service Manual

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

)

(Cont’d)

Troubleshooting  Guide

The following troubleshooting guide is provided for
assistance in locating and correcting BICS system
problems. It is recommended that these procedures be
done by authorized Bobcat Service Personnel only.

BICS CONTROLLER

W–2004–1285

Check for correct function after adjustments,
repairs or service. Failure to make correct
repairs or adjustments can cause injury or
death.

  1.

Check that ignition switch ON.

  2.

Check BICS 10 amp. fuse.

  3.

Check  wiring  and connections. Make sure the connector is securely connected
to the controller. Remove controller and pull on connector to check.

  4.

Look at indicator light windows, if they are milky white in appearance it is most
likely caused by moisture in the controller. Allow to dry or replace the controller.

  5.

Refer to BICS troubleshooting chart for your loader. (See Page 8–4 & 8–7.)

  6.

Check wire connections to make sure connectors are locked into place.

  7.

Check pins in connectors for pins pushed back or bent.

  8.

Move the system wiring back & forth to try to find area that may be causing the
intermittent connection.

  9.

Use sensor tester MEL1428 to isolate problem between sensor and controller
and wiring.

PROBLEM

SOLUTION #

Power indicator light does not come ON.

1, 2, 3, 6

All indicator lights flashing.

4

One of the indicator lights flashing.

5

Intermittent indicator lights.

6, 7, 8, 9

SOLUTION SUGGESTIONS

Revised June 01

–8–8–

773 BICS Loader

Service Manual

BOBCAT INTERLOCK CONTROL SYSTEM (BICS

™

)

(Cont’d)

Troubleshooting Guide (Cont’d)

The following troubleshooting guide is provided for
assistance in locating and correcting BICS system
problems. It is recommended that these procedures be
done by authorized Bobcat Service Personnel only.

TRACTION LOCK

W–2004–1285

Check for correct function after adjustments,
repairs or service. Failure to make correct
repairs or adjustments can cause injury or
death.

  1.

Check that controller power indicator light is ON.

  2.

Make sure brake pedal is not engaged.

  3.

Maneuver loader to allow brake discs to move and remove pressure on the brake
wedge so it can retract.

  4.

If all lights indicate the brake should be released, but it doesn’t, check the brake
25 amp. fuse.

  5.

When checking fuse, also check other fuses. Check the fuse block for correct
orientation and location of fuses. (See Electrical System, Page 6–1.)

  6.

To test the solenoid, the pull coil should be 0.4 to 0.5 ohms and the hold coil 10.5 to
11.0 ohms.

  7.

Check brake solenoid and cover mounting hardware for the correct torque.

  8.

Remove brake cover and check wedges for binding in the wedge guides.

  9.

Check wire connections for loose connector body.

10.

Check for loose or bent pins in connectors.

11.

Check for loose spade connectors in fuse holder.

PROBLEM

SOLUTION #

Traction lock stays engaged.

1, 2, 3, 4, 5, 6, 7, 8

Intermittent activation of traction lock.

9, 10, 11

SOLUTION SUGGESTIONS

Revised Jan. 99

773 BICS Loader

–8–9–

Service Manual