Head Unit Troubleshooting

Head Unit (HU20) – Troubleshooting

Applies to: Head Unit HU20, with GreaseBoss Grease Tags and a Fixed Plant Gateway. HU14 is discontinued and not covered here.

Scope: The Head Unit and the GreaseBoss system, including the grease path through the Head Unit. Not the machine being greased — a blocked nipple or a packed bearing is for your site maintenance team.

How it works: Head Unit Explained – Manual System (Version 2.0) and Manual System – GreaseBoss Head Unit (HU20).

DIAGNOSTIC STEPS

Step 1 — Start here

(Click on a "Part" in the table below to navigate to that section)

Go to	What you're seeing
Part A — Power and charging	Screen blank, or the unit won't respond
Part B — Won't read a tag	Screen works, but no point name and no blue LED
Part C — Reads, but the wrong information is displayed	"No task found", wrong grease, or a QR code and RFID number
Part D — Syncing to GreaseCloud	Works in the hand, but GreaseCloud shows Offline or is missing data
Part E — Grease delivery and measurement	Little or no grease delivered, or grease delivered but not counted
Not a Head Unit fault	Grease flows freely off the nipple, but the point won't take it. Refer to your maintenance team
Symptom / Likely Cause / Suggested Action	Quick Reference Table

PART A — POWER AND CHARGING

What you're seeing: the screen is blank, or the Head Unit doesn't respond when you try to use it.

A blank screen is a fault — the HU20 keeps its screen on at rest. The front-light comes on when the unit wakes or reads a tag, and either button wakes the screen.

Step A1 — Charge the Head Unit

Confirm the screen is genuinely blank — press either button to check.
Connect the 12V charger. A light on plug-in confirms power is reaching the unit.
Leave it on charge 4 hours; a deeply flat battery shows nothing at first.
Screen comes up → go to Step A3.
No light on plug-in → try the charger on another Head Unit.
- The other unit charges → this Head Unit is at fault. Go to "Still not working".
- Neither charges → replace the charger or lead.

Step A2 — Battery won't hold charge

Check the battery indicator — five increments, plus a charging icon while on charge.
Confirm the charging icon stayed on for the full 4 hours.
Charged full, then flat within a shift → battery fault. Go to "Still not working" with the serial number and firmware version.
Used below −10°C or above 50°C → shorter run time is expected.

Step A3 — Return the Head Unit to service

Charge it within Gateway range — a unit on charge syncs roughly every 2 hours.
Confirm the battery holds over the next shift.
Confirm a recent Last Activity at Dashboards > Health > Head Units.

PART B — WON'T READ A TAG

What you're seeing: you present the coupler to a tagged grease point and nothing happens — no point name on the screen and no blue LED.

The RFID reader sits in the handle. The metal wand and coupler act as its antenna, earthed through the grease nipple — so grip and coupler seating are part of the read path.

Step B1 — Check the Head Unit is awake

A Head Unit in sleep mode will not read tags. The screen shows either:

"Asleep" at the top, with the rest of the display still showing, or
"Press button to start", with the time of the last sync.

Step B2 — Check how the gun is being held

The most common cause — a hand around the wand or dog leg shields the antenna.

Hold the nozzle by the handle only.
Seat the coupler on the nipple first.
Hands off all metal — wand, dog leg, coupler, extensions.
Wait for the read — point name and blue LED — before pumping grease.
Reads → resolved. Brief the crew on the technique.

Step B3 — Check the coupler is seated on the nipple

The coupler earths through the nipple, so partial contact breaks the read path.

Fully engaged and square on the nipple, not part-way on or at an angle.
The coupler suits the nipple fitted at that point.
Both clear of packed grease, paint, corrosion and damage.
Reads once seated → resolved.

Step B4 — Direct-read test

Separates a faulty reader from a broken antenna path.

Touch the tag to the base of the handle, where the wand exits.
Reads → the reader works. The fault is the antenna path (B3) or the tag (B5).
Doesn't read → go to Step B6.

Step B5 — Check the tag and its mounting

Rotate the tag on the nipple — a small change in position is often enough.
The tag needs metal close behind it, or it may never read reliably.
Check it is intact, clean and not painted over.
Confirm the variant suits the fitting — Snap Fit and Snap On for Zerk, Button Head V-Tags for button head.
Try another Head Unit at the point, and this one elsewhere.
Tag lost or damaged → see Replace a lost tag.

Step B6 — Work out how widespread it is

One point only → the tag or its mounting. Back to Step B5.
Every point, and the direct-read test fails → reader fault. Go to "Still not working".

PART C — READS, BUT THE WRONG INFORMATION IS DISPLAYED

What you're seeing: the tag reads, but the screen shows something you weren't expecting — no task due, the wrong grease, or a QR code instead of the point name.

Step C1 — "No task found"

Expected when no task is due. Skip the point.
An out-of-date schedule shows this even when a task is due. Sync the unit (Part D) and try again.
Schedules update separately, so one can be stale while others are current.
Every point on the asset → no schedule applied. Site admin to check in GreaseCloud.

Step C2 — "WRONG GREASE"

Stop. Tell your supervisor if any grease has gone in.
Check the grease set for the Head Unit: Dashboards > Health > Head Units > serial number > Consumable.
Check the grease set for the grease point / Grease Tag in GreaseCloud. Either can be wrong.
Either is wrong → site admin corrects it.
Both correct → the gun holds the wrong grease. Use the correct gun.

Step C3 — QR code and RFID number on the screen

The Head Unit shows a QR code and the tag's RFID number when the tag isn't mapped to a grease point.
Have the point mapped in the GreaseBoss mobile app, then try again.
In GreaseCloud, greasing at an unmapped point — or with no tag read — records against "00000000000000" or an unknown point.
Recurring at a mapped point → the tag isn't reading. Go to Part B.

PART D — SYNCING TO GREASECLOUD

What you're seeing: the Head Unit works normally in the hand, but GreaseCloud shows it Offline, or greasing you know was done isn't there.

The Head Unit doesn't sync while in use. It stores greasing and uploads it at the next sync — roughly every 2 hours on the charger, or 1am off it. Long gaps are normal.

Step D1 — Check whether a sync window has passed

Greasing at 10am with the unit off the charger won't appear until after 1am, not that morning.
None passed yet → no action. Check after the next sync.

Step D2 — Check Last Activity, not the Online dot

Go to Dashboards > Health > Head Units and find the serial number.
The Inactivity Timeout is 7 days, so Online only means it synced sometime in the last week.
Last Activity recent → Step D4. Older than expected → Step D3.

Step D3 — Check the charging location and the Gateway

Is the Head Unit charged within Gateway range? Guidance is up to approximately 5 m.
Check a Gateway signal is present in that area.
Check the Gateway's status at Dashboards > Health > Gateways.
- Offline → fix the Gateway first; the Head Unit can't sync through it.
- Online → move the charging point closer, or ask GreaseBoss about coverage there.
Site power off, or asset shut down → expected. It syncs when power and coverage return.

Step D4 — Check the Head Unit sync timeline

Click the serial number, open the Timeline tab.
Orange Device Info Events = synced to a Gateway. Not a cloud sync — the Gateway passes the data on.
Dark Flow Events = greasing recorded. Far fewer than sync events.
Orange at the normal rate, no Flow Events → communicating, not recording greasing. Part B or Part C.
Orange stopped → Step D3.
About one orange event a day → normal for a unit that lives off the charger.

Step D5 — Confirm the fix

Wait for the next sync window, then allow 10–20 minutes for data to appear.
Confirm Last Activity is recent, orange events resumed, and the greasing shows.

PART E — GREASE DELIVERY AND MEASUREMENT

What you're seeing: you pump and little or no grease comes out — or grease clearly goes in, but the Head Unit doesn't count it.

The Head Unit sits in the grease path between the gun and the nipple, and measures the grease passing through.

Safety: grease at these pressures can inject through skin. Never test flow against any part of your body, and relieve pressure before disconnecting anything.

Step E1 — Find out where the flow stops

Take the coupler off the nipple and pump into a rag or waste container.
Grease flows freely → the gun and Head Unit are delivering; the point won't take grease. Out of scope — refer to your maintenance team, and don't pump against a blockage.
Little or no grease → go to Step E2.

Step E2 — Check the grease gun

Check the cartridge or canister isn't empty.
Prime or bleed the gun per its manufacturer's instructions — an air lock stops flow even with a full cartridge.
Grease flows → resolved. Still none → go to Step E3.

Step E3 — Check the joint between the Head Unit and the gun

Look at the joint where the Head Unit screws onto the grease gun adaptor.
Grease escaping → the JIC fittings aren't sealing. Relieve pressure, tighten with spanners, try again.
No leak, still no grease → go to Step E4.

Step E4 — Isolate the Head Unit from the gun

Relieve pressure, remove the Head Unit, and pump the gun on its own.
Grease pumps from the gun → the restriction is inside the Head Unit. Go to "Still not working". Don't raise the pressure to clear it.
No grease from the gun either → grease gun fault, not the Head Unit. Repair or replace the gun.

Step E5 — Grease flows, but it isn't being counted

The tag has read and the point name is on screen, but the volume doesn't climb and the unit never reaches its target.

Check for grease escaping at the joint to the gun (Step E3) — a leak means little grease passes through the unit.
Check whether it happens at other points.
One point only → the target volume is probably too high. Site admin to review it.
Every point → likely a flow measurement fault. Go to "Still not working" with the serial number and firmware version.

SYMPTOM / LIKELY CAUSE / SUGGESTED ACTION

Symptom	Likely Cause	Suggested Action
Screen on but not lit up	The unit is at rest	Press either button to wake the screen. The front-light also comes on when a tag is read
Screen blank, unit won't respond	Flat battery	Charge for 4 hours on the 12V charger, and check for the light on plug-in (A1)
No light when plugged in	Charger, lead or outlet fault	Test the same charger on another Head Unit (A1)
Flat within a shift after a full charge	Battery or hardware fault	Contact Support with the serial number and firmware version
"Asleep", or "Press button to start", on screen	Unit in sleep mode — it won't read tags	Press either button to wake it, then try the read again (B1)
Won't read, hand wrapped over the wand or dog leg	Hand shielding the antenna	Hold by the handle only, hands off all metal, wait for the read (B2)
Won't read at one point only	Coupler not seated, or the tag has no metal behind it	Check the coupler, and rotate or check the tag (B3, B5)
Won't read since a coupler or nipple was changed	The coupler no longer seats squarely on the nipple	Confirm the coupler suits the nipple fitted (B3)
Won't read anywhere, and the direct-read test fails	Reader or hardware fault	Contact Support
"No task found"	No task due at that point	Expected. Skip it. If a task is due, sync the unit and check the schedule (C1)
"No task found" at every point on an asset	No schedule applied to those points	Site admin to check the schedule in GreaseCloud
"WRONG GREASE"	Grease set for the Head Unit or the point doesn't match the gun	Stop. Check the Consumable and the point's grease in GreaseCloud (C2)
QR code and RFID number on screen	The tag isn't mapped to a grease point	Map the point in the GreaseBoss mobile app (C3)
GreaseCloud shows "00000000000000" or an unknown point	Greasing at an unmapped point, or no tag read	Map the point, or work through Part B
No greasing in GreaseCloud a few hours after the job	The unit hasn't synced yet	Expected. Off the charger it syncs at 1am (D1)
Last Activity a day old, every day	The unit lives off the charger and syncs nightly	Expected. Charge it within Gateway range for more frequent syncs
Shows Online, but the data is stale	7-day timeout — Online isn't a recency check	Read Last Activity instead of the Online dot (D2)
Orange Device Info Events have stopped	The unit isn't reaching a Gateway	Check the charging location and the Gateway's status (D3)
Syncing normally, but no Flow Events	Communicating, but not recording greasing	Go to Part B or Part C
Nothing at the point, but grease flows off the nipple	The grease point won't take grease	Out of scope. Maintenance team. Don't pump against a blockage
No grease off the nipple either	Empty cartridge, air lock, restricted Head Unit or faulty gun	Work through Part E in order
Grease escaping at the joint to the gun	JIC fittings not sealing	Relieve pressure and tighten the fittings with spanners (E3)
Grease pumps from the gun alone, but not through the Head Unit	Restriction inside the Head Unit, often hardened grease	Contact Support. Don't raise the pressure to clear it (E4)
No grease from the gun with the Head Unit removed	Grease gun fault	Repair or replace the gun
Grease flowing at every point, but nothing counted	Flow measurement fault	Rule out a leak at the gun joint, then contact Support (E5)
Never reaches target at one point only	Target volume set too high for that point	Site admin to review the target in GreaseCloud

STILL NOT WORKING

Contact GreaseBoss Support with:

Site, asset and grease point
Head Unit serial number (e.g. GBHU2006XO) and firmware version
The symptom, and the steps you have already tried
A screenshot of the unit's row in Dashboards > Health > Head Units, and of its Timeline
Read failure: a photo of the tag in position on the machine, and of the coupler on the nipple
Flow fault: whether the gun delivers grease with the Head Unit removed, the grease in use, and a photo of any leak

Email: support@greaseboss.com.au