JoeGuardian Automation

2. FANUC Teach Pendant Navigation: The Screens Every Technician Must Know

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Introduction

Once you understand what the FANUC Teach Pendant is, the next step is learning how to navigate the most important screens.

For an automation technician, the goal is not to memorize every menu on day one. The goal is to know where to go when the robot stops, how to find useful information, and how to avoid changing something by mistake.

In a real production environment, the pendant helps you answer these questions:

Why did the robot stop?
What program was running?
What line stopped?
Is the robot waiting for a signal?
Is the problem related to safety, I/O, motion, gripper, PLC, or product position?

This post focuses on the main Teach Pendant screens that every technician should know.

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1. The Technician Navigation Mindset

When a robot is down, do not start pressing buttons randomly.

Use this sequence:

Alarm → Program → Line → I/O → Position → Jog → Step Test → Auto

This sequence gives you control of the situation.

Step	Purpose
Alarm	Find why the robot stopped
Program	Find what routine was running
Line	Find the exact instruction where it stopped
I/O	Check signals from sensors, PLC, gripper, and safety
Position	Check where the robot is physically located
Jog	Move the robot manually if needed
Step Test	Test one instruction at a time
Auto	Return to production only after safe verification

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2. Alarm Screen

The Alarm Screen is the first place to check when the robot stops.

What to look for

When you open the alarm screen, identify:

Alarm code
Alarm message
Alarm type
Active or historical alarm
Time of alarm
Whether it returns after RESET

Common alarm families

Alarm Type	General Meaning
SRVO	Servo, motor, axis, brake, safety, or motion-related issue
MOTN	Motion not allowed or motion error
INTP	Program execution or interpreter issue
SYST	System-level issue
TPIF	Teach Pendant or interface issue
Collision Guard	Robot detected abnormal force
Overtravel	Axis moved beyond allowed limit
Safety	E-stop, gate, fence, scanner, or enabling device issue

Important rule

Do not treat the RESET button as the solution.

RESET only clears the alarm if the real condition is corrected.

Example:

Alarm: Fence Open

Pressing RESET will not solve the issue if the safety gate is still open or the interlock is not satisfied.

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3. Program Select Screen

The Program Select Screen shows the available robot programs.

This is where you usually find programs such as:

MAIN
HOME
PICK
PLACE
PALLET
RECOVERY
GRIPPER_OPEN
GRIPPER_CLOSE
AUTO_START

What technicians should look for

Item	Why It Matters
Active program	Shows what the robot was running
Main routine	Usually controls the overall cycle
Subprograms	Smaller routines called by the main program
Recovery program	Used to recover the robot safely
Home program	Sends robot to a known safe position
Program comments	Help identify the purpose of each routine

Practical example

You may see:

MAIN
PICK_BOX
PLACE_BOX
HOME_POS
RECOVERY

If the robot stopped while handling a box, the active program may be PICK_BOX or PLACE_BOX, but the main sequence may be controlled by MAIN.

That is why it is important to know not only the selected program, but also the current line where execution stopped.

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4. Program Edit Screen

The Program Edit Screen shows the actual robot instructions.

This is one of the most important screens for troubleshooting.

Example:

1: UFRAME_NUM=1 ;
2: UTOOL_NUM=2 ;
3: J P[1] 50% FINE ;
4: L P[2] 500mm/sec CNT50 ;
5: DO[10]=ON ;
6: WAIT DI[12]=ON ;
7: L P[3] 250mm/sec FINE ;
8: DO[10]=OFF ;

How to read this

Instruction	Meaning
UFRAME_NUM=1	User Frame 1 is active
UTOOL_NUM=2	Tool Frame 2 is active
J P[1]	Joint move to position P[1]
L P[2]	Linear move to position P[2]
DO[10]=ON	Turn ON digital output 10
WAIT DI[12]=ON	Wait until digital input 12 turns ON
FINE	Stop exactly at the point
CNT50	Blend through the point smoothly

Technician focus

When troubleshooting, look for:

WAIT DI[x]
WAIT R[x]
DO[x]=ON/OFF
CALL program_name
J P[x]
L P[x]
IF condition
LBL/JMP

A robot stopped on a WAIT DI[x]=ON line is often waiting for a real-world condition.

That condition may come from:

• PLC
• Sensor
• Gripper
• Vacuum switch
• Conveyor
• Safety system
• Product detection
• Pneumatic device

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5. Current Line Number

The current line number is critical.

It tells you exactly where the robot stopped.

Example

Robot stopped here:

15: WAIT DI[25]=ON ;

DI[25] is labeled:

Gripper_Closed

This means the robot is waiting for confirmation that the gripper closed.

Possible causes:

Possible Cause	What to Check
Gripper did not close	Check air, cylinder, solenoid
Sensor not made	Check proximity/reed switch
Product misaligned	Check box/container position
Output not energizing	Check robot DO to solenoid
Air pressure low	Check regulator and supply
Cable issue	Check sensor wiring
PLC condition missing	Check PLC permissive if signal comes from PLC

This is why the current line is so powerful. It tells you what the robot expected to happen.

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6. I/O Screen

The I/O Screen is where technicians solve many robot problems.

Robots communicate with:

• PLC
• Sensors
• Gripper
• Vacuum system
• Conveyors
• Safety devices
• Machine modules

Common robot inputs

Input Signal	Meaning
Part Present	Product is ready
Box In Position	Box is located correctly
Gripper Opened	Gripper open sensor is ON
Gripper Closed	Gripper closed sensor is ON
Vacuum OK	Vacuum level is acceptable
Conveyor Ready	Conveyor is ready
Safe To Pick	PLC permits robot to enter
Safe To Place	PLC permits robot to place
Cell Ready	Cell conditions are satisfied
Fault Reset Request	Reset request from PLC or HMI

Common robot outputs

Output Signal	Meaning
Robot Ready	Robot is ready
Robot Running	Robot is executing
Robot Faulted	Robot has an alarm
Robot Home	Robot is at home position
Robot Busy	Robot is in cycle
Pick Complete	Pick sequence completed
Place Complete	Place sequence completed
Gripper Open Cmd	Command to open gripper
Gripper Close Cmd	Command to close gripper
Vacuum On Cmd	Command to turn vacuum ON

Practical I/O troubleshooting method

When the robot is waiting for a signal:

1. Identify the DI number.
2. Read the DI comment/name.
3. Check if the signal is ON or OFF.
4. Check the physical device.
5. Check the PLC input/output if applicable.
6. Check the robot I/O mapping.
7. Check wiring, air, sensor, or mechanical condition.

Example:

WAIT DI[30]=ON
DI[30] = Box_At_Pick_Position

If DI[30] is OFF:

• Check photo eye.
• Check box position.
• Check sensor LED.
• Check conveyor indexing.
• Check PLC logic.
• Check cable or input module.
• Check if the robot is looking at the correct signal.

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7. Position Screen

The Position Screen shows where the robot is.

You may see the robot position in different formats:

Cartesian position

X = 1200.000
Y = 450.000
Z = 350.000
W = 180.000
P = 0.000
R = 90.000

Joint position

J1 = 15.000
J2 = -35.000
J3 = 45.000
J4 = 0.000
J5 = 90.000
J6 = 180.000

Cartesian vs Joint

Type	Use
Cartesian	Useful for X/Y/Z position adjustment
Joint	Useful for seeing robot axis angles
Cartesian Z	Often used for height adjustment
Joint J1-J6	Useful for manual recovery and avoiding awkward posture

For pick-and-place applications, Cartesian position is especially important because height changes are usually made in the Z direction, depending on the active frame.

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8. DATA Screen

The DATA Screen is where you can find registers and position registers.

This is important because many robot programs do not use only fixed positions.

They may use:

R[x]    Numeric Register
PR[x]   Position Register
P[x]    Program Position

Registers

Numeric registers store numbers.

Example:

R[10] = 25.0

This could represent:

• Stack height
• Layer number
• Product count
• Offset distance
• Recipe value
• Speed value
• Delay time

Position Registers

Position registers store position data.

Example:

PR[20] = Pick_Offset
PR[30] = Place_Height
PR[40] = Recovery_Position

Position registers are commonly used for:

• Offsets
• Palletizing
• Recipe adjustment
• Height adjustment
• Calculated positions
• Shared positions between programs

Important technician rule

Before changing anything in DATA, write down the original value.

Example:

Before:
PR[30] Place_Height
X = 1000.000
Y = 500.000
Z = 350.000
W = 180.000
P = 0.000
R = 90.000

If you change Z from 350.000 to 360.000, document it.

After:
Z = 360.000

This allows you to return to the original value if needed.

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9. Coordinate Screen / COORD Button

The coordinate system determines how the robot moves when jogging.

This is one of the most important concepts for beginners.

Common coordinate systems

Coordinate Mode	Description
Joint	Moves one robot axis at a time
World	Moves relative to the robot/world coordinate system
Tool	Moves relative to the tool orientation
User	Moves relative to the user-defined work area
Jog Frame	Custom jogging coordinate system, if configured

Practical meaning

If you press +Z, what happens?

It depends on the active coordinate system.

Mode	What +Z May Do
World	Move upward relative to world
User	Move upward relative to the user frame
Tool	Move along the tool’s Z direction
Joint	Not applicable as X/Y/Z; moves selected joint

For height changes, technicians usually need to understand whether the robot is using World, User, or Tool.

In many pick-and-place applications:

Z+ = move up
Z- = move down

But this depends on the frame setup. Always verify with small movements at low speed.

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10. Speed Override Screen / Button

The speed override controls how fast the robot moves.

When troubleshooting, recovering, or teaching positions, use low speed.

Recommended for beginners:

5% to 10%

Use higher speed only when you are confident and the path is clear.

Never move fast near:

• Conveyor
• Box
• Container
• Pallet
• Gripper
• Safety fence
• Machine frame
• Sensors
• Air lines
• Other equipment

Speed override is one of the easiest ways to reduce risk during recovery.

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11. Step Mode

STEP mode lets you execute the program one instruction at a time.

This is very useful after:

• Alarm recovery
• Position adjustment
• Robot crash
• Product jam
• Bad pick
• Bad place
• Gripper issue
• Program change

Example

Instead of running the full program in AUTO, you can step through:

1. Move to approach position
2. Open gripper
3. Move to pick position
4. Close gripper
5. Wait for gripper closed
6. Move up
7. Move to place position
8. Open gripper
9. Wait for gripper opened
10. Return home

This makes troubleshooting more controlled.

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12. Screens You Should Avoid Changing at First

Not every screen is safe for beginners.

Avoid changing these unless you are trained, authorized, and have a backup:

Area	Why Be Careful
System Variables	Can affect robot behavior globally
Mastering Data	Incorrect values can cause position errors
Frames	Changes affect many positions
Tool Data	Affects robot path and orientation
Payload Data	Affects motion performance and collision detection
I/O Mapping	Can break robot/PLC communication
Safety Configuration	Can create serious hazards
UOP Configuration	Can affect AUTO operation
Program Select Setup	Can affect production start sequence

You can view many of these areas for troubleshooting, but do not modify them casually.

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13. Real Plant Example: Robot Stopped After Picking a Box

Symptom

The robot picks a box, moves up slightly, then stops.

Pendant shows

WAIT DI[18]=ON

DI[18] comment:

Vacuum_OK

Interpretation

The robot is waiting for confirmation that vacuum is strong enough.

Possible causes

Cause	Check
Vacuum cup damaged	Inspect cups
Air supply low	Check regulator
Product surface leaking	Check box/container condition
Vacuum sensor not adjusted	Check sensor threshold
Solenoid not activating	Check DO command
Hose leaking	Inspect tubing
Filter clogged	Check vacuum generator/filter
Product not centered	Check pick position

Technician action

1. Check DI[18] on the I/O screen.
2. Check if Vacuum_ON output is active.
3. Check physical vacuum device.
4. Check sensor LED.
5. Check air pressure.
6. Check gripper contact with product.
7. Correct the issue.
8. Reset alarm if needed.
9. Test in STEP mode.

This is a good example of using pendant navigation to find the real cause.

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14. Basic Navigation Checklist

Use this checklist every time you approach a stopped robot.

1. Check that the area is safe.
2. Read the alarm screen.
3. Write down the alarm code.
4. Find the active program.
5. Find the current line.
6. Identify if the robot stopped on WAIT, motion, CALL, or I/O.
7. Check relevant inputs and outputs.
8. Check robot position.
9. Verify product, gripper, air, and sensors.
10. Correct the real cause.
11. Reset only after correction.
12. Jog slowly if recovery is needed.
13. Run in STEP mode before AUTO.
14. Return to AUTO only after safe verification.

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15. What to Practice This Week

For this lesson, practice navigation only. Do not modify positions yet.

Practice tasks

1. Open the alarm screen.
2. Open the program list.
3. Open the active program.
4. Find the current line.
5. Open the I/O screen.
6. Search for a DI signal.
7. Search for a DO signal.
8. Open the position screen.
9. Change between Joint, World, Tool, and User jog mode.
10. Lower the speed override.
11. Enable STEP mode.
12. Observe the robot sequence one line at a time.

The goal is to build confidence without making unsafe changes.

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Conclusion

The Teach Pendant becomes much easier when you know which screens matter first.

For a technician, the most important screens are:

Alarm Screen
Program Screen
Current Line
I/O Screen
Position Screen
Data Screen
Coordinate Mode
Speed Override
Step Mode

When the robot stops, use a structured troubleshooting path:

Alarm → Program → Line → I/O → Position → Cause → Reset → Step Test → Auto

This method helps you avoid guessing and helps you troubleshoot like a professional automation technician.