Automower 435X AWD, Husqvarna, review.

This Automower 435X AWD is an upgrade from my 330X, See review here.

Overall: 9/10. Hardware: Fine. Software: Improved, still unpolished!

This is both a continuation of the previous Automowers and a fundamentally different approach

Updated 2020-04-29, Some stuff are fixed with newer firmware.

2020-08-05 This review has evolved over time from an early review, with several updates, so bare with me, that things are not in a straight chronological line…

2020-09-05 Updated with new stuck-bug

The main difference over previous automowers is that it comprises of two parts, with All Wheels Drive (=AWD)

The two parts can move ‘freely’ along two axis. The small part can turn 90° in both side directions, and also tilt somewhat to keep grip on all four wheels, even on uneven terrain.

This all means that it can climb steeper and more uneven terrain than the previous models, they claim 70% (35°)

…and a photographer can make that look really steep:


What garden-type is this model for?

If you got a normal flat garden, you gain absolutely nothing from this model over their other high end models. It would be like driving an off-roader on a highway, it works, but nothing is gained! (If anything waste of energy). And it can be harder for it to go around narrow passages. Like small trees in the lawn close together or close to the bounding wire. It is like navigating a car with a trailer.

But if you got a garden with steep slopes or very uneven terrain you will love the better terrain handling. Again think where you would like an off-roader to drive.

(They also got a sister model the 535X AWD, intended for professional usage in a fleet of mowers, but the important parts are identical)


Under the hood

Here a nice image from of an unused one (click to enlarge)


The cutting system is a slight modification of the already great silent system they have used on the 330X, the blades are the same size, but mounted on a 2cm narrower disk, and the blank protection plate under is 1cm less, so the blades are sticking out about 5mm less each. It does surprisingly not seem to deteriorate the cutting, but it should make it even harder to get injured, even if you manage to get under it despite the security systems. It detects both bumping into stuff and if the shield is lifted. It even got a pair of ultrasonic sensors in the front part, and if anything gets within range, it slows down. On the above image you can also see the four circles on each of the two parts, these are the bases of the eight ‘joysticks’ that should detect any horizontal bumps to the shields.



Experiences so far

It has had ZERO problems with climbing my uneven and slopped garden, and it has only once in over a month year got stuck digging holes in the ‘lawn’ – the second day actually, in an existing mud-hole dug by the 330X. (A really annoying bug that was introduced to the 330X on a software ‘upgrade’, as mentioned in the review).

The previous models were like older cars with the motors on the rear wheels pushing it forwards, and two passive small wheels at the side of the cutting system. This gave them a tendency to lift the front in steep terrain.

The AWD system gives more weight on all wheels as well as better traction.

(It does add its own problems – more on that later…)


The noise level of the 435X is given as 62dB versus the 58dB of the 330X . But the picture is a bit more complex, as it is more silent than the 330X when it is just driving around, so it is the cutting noise in dense grass that is higher. Actually you do not really hear the driving motors, but you do hear what I assume is cooling, as the noise not cutting seems identical when it reaches the boundary wire stops and reverts.


A nice detail: When it reaches the boundary wire at a shallow angle, it does NOT do a turning manoeuvre, but just make a fairly smooth turn. When it turns at a sharper angle, it looks similar to what you would do with a car with a trailer.


One other great thing out-of-the-box is Automower Connect (AMC). It is a GSM module in the mower (ten years prepaid), and an app (Android/Ios) for mobiles.

AMC was available for the 330X too, as a £2K accessory that I was too stingy to buy.


The 435X can to some extent be operated by a “Jogwheel”, but this is REALLY a pest, and luckily you do not need to use it in daily usage, only for initial set-up.

One other bad thing is the extra weight and unhandy carrying by design.
The older models you carried by lifting the back end, carrying with the top close to you, and the weight was about 13Kg.
But this is designed to carried horizontally so you are easily getting rather smudged unless you carry it away from the body, and by 17.3Kg, it is not for weaker old ladies to carry it say 50m uphill through the garden that way… BUT you can carry it somewhat similar to the old ones! With the top of the broad front part resting on the side of your leg, and the small part ‘dangling’ upwards. It looks a bit silly but is much easier for an old fart like me, to carry without getting smudged….


and in reality


This should only be needed if the mower can not find home and runs out of battery, or on severe errors requiring you to have it serviced.

(update: And though that was quite often with the initial software, that is much more seldom in 2020)


Like the 330x and unlike the 235ACX the 435X has a bad physical top design (and they just got a Red Dot Award!!!), as low hanging branches of trees or a hedge catches the stop handle. It has happened once or twice every week. (And as the app ‘thinks’ a human pressed the stop, you do not even get notified that the mower got caught, a simple warning after say 30 minutes where it was neither lifted or moved after stop, would do the trick – unfinished software…)

The automatic spot cutting of he 230ACX and 330X seems to be missing, it could be quite handy, if the mower has been inactive for a short while and/or if there is an area that have grown particularly fast. My guess is that it is simply harder to do in a nice way with a model where manoeuvring is not that easy.

It primarily drives with the broad part (holding the cutting motor) in front. but can freely mow in both directions. When searching for the docking station along the guide wire it goes with the small ‘rear’ part first.



The principal idea and many of the pros and cons, are the same as the earlier ones, so if you are new to Automowers you should check the old review here too for Pros and Cons.


Unfinished software

The Automower software is currently very unfinished, so Husqvarna Denmark has been reluctant to even allow the dealers to actually sell the new mowers late summer of 2019, despite they have had them in stock since April 2019!!

New software with major fixes is not expected until October 2019!!

One of the HUGE bugs (seen from my perspective) is that it can only go to the charging station by a guide-wire, it can not currently follow the boundary-wire in, as a last resort, as the previous ones. So I had to add a cable in the lawn for this. And this means that I a few times (three in the first month) have needed to carry it to the docking, because I have only added one guide, and it is not crossing the entire garden. But they promised this will be fixed.

Update 2020-04-29: Fixed

There are also some navigating bugs when it navigate in closed places, e.g. a tree close to the edge of the lawn. It often ends in a situation where it claims “collision error”, but a simple manually triggered retry, and it more often than not gets free, so a few more retries before giving up would be nice…

Update 2020-04-29: Improved

One of the expected upgrades is that it should forthwith offer OTA updates, previously models updates required a PAID visit to the dealer.

Update 2020-04-29: Fixed

To detect if spot cutting was needed on the older models they measured how much work the cutting motor did.
As I assume that circuitry is still there, it would be SO obvious to use this for some automatic season/weather adjustments, by simply determine when it should leave after charging depending on how much work it has been doing the last few cycles. If a lot of work then leave as quickly as possible,  if very little then wait longer before mowing again.

Also you can get quite detailed local weather forecasts online, so that COULD be used so that it only mowed in rain if it really needed to, I mean if you got a 1000m² lawn it could try to primarily run when the grass is dry. It runs fine in rain, but it would be smart if it only did when needed.

Another issue (that I ASSUME is due to poor software and not poor hardware): The self-discharge on idle (e.g. after an error), is at the least 1% per hour(!). So you can easily go from a simple error that just needs a retry, to needing to carrying it for charging if you are away for a day or a weekend….
Update 2020-05-29. Per default it flashes the headlights on error. Surprisingly this function is a major culprit in wasting battery, so I will STRONGLY urge people to turn this off, especially if they often are away for a whole day. We got the GPS with a rough estimate of where it is stuck in the app, so turn the flash function on only if you strictly need it. (Say a garden with a lot of dense vegetation overgrowing the lawn in low height, so the mower can be hard to spot from the last reported GPS position – that can be 10m off)


Automower Connect (AMC) App

The Connect software is not very buggy as such, but allows for much less than they could, e.g. too many errors does NOT allow for a retry from within the app. You need to go to the mower, press stop and start, and then retry from the app…

One REALLY handy feature of the app is that it can tell where the mower is (roughly). This is of course especially useful if you are not just having one flat continuous lawn (And if you do, you should buy a simpler Automower model). This is a HUGE improvement over the 330X – so I should have bought that for the 330X… Silly me…

Another great feature is that you get a notification within minutes or even seconds when something is wrong. Or rather you are supposed to get a notification, often it does not appear, even hours after. But if you then open the app it does. (And yes I have excluded the app from optimizations…)

The app also allows for connection through Bluetooth, and that is fine.

BUT for some odd reasons some features are ONLY allowed through Bluetooth. That simply is meaningless, as all security is bound to the pin anyway, so they could just request re-entering the pin to access these parts.

The worst BUG (or should  be kind and call it “lacking feature”) is that when the mower requests a pin you MUST enter it with the horrible jogwheel, you are NOT allowed to do it in the app. There are ZERO excuse for this! You could even argue that this requirement LOWERS the security. If you are away and say a neighbour sees the machine is stuck, and calls you (or you see the error in the app and call him), you will need to give him the pin, rather than enter it remotely yourself…

There is one bug that is quite odd: IF you try to connect to it via Bluetooth while it’s mowing, it claims the pin to be wrong! But if you turn off BT on the phone, things work again over the GSM module.
If the mower is stopped with an error or is in the docking, THEN you can connect with BT.

Update 2020-04-29: To make thing worse I can not get the software working over BT with any other model I tried than my ageing Samsung S8- I have tried several other Android/LineageOS phones and they all pair just fine BT-wise, but the software does not accept that it is paired on any but the S8-.

Sometimes AMC reports something odd when opened, then you ‘just’ have to ignore it, and kill the app (Android: Settings, Apps, AMC, Stop) and start it again. (e.g. stuck reporting last error message)

It would be SO obvious to allow for navigation of the mower in the app, to have it go (or not go) somewhere. But nothing like that is offered at all.

The only actions you can send is Stop, Park, and Start. Plus you can change settings like timer windows, and adjust the cutting height.

It would also be SO obvious to have a way to fence part of the lawn off, temporarily while still doing the rest of the lawn. Rather than having to stop it completely. Should be really easy to ROUGHLY fence off parts of the garden temporarily – say while you are cutting a hedge, or trimming edges.

In the stick-splitting department: When charging the icons are reflecting the truncated values of the percentages (not the rounded) – at the least up to around 90% (The app only updates the display every 5%).
Also note how the predicted “Next start” are off with a quarter of an hour, until the very last where it actually starts (bellow 99%, 100% and Mowing are all at 13:37, yet at 100% it still predict “Next start 13:50″…

They display 24% as 0/4 , 49% as 1/4 as 74% 2/4…
The natural thing would have been to display 0-12% as 0/4, 13-37% as 1/4, 38-62% as 2/4, 63-87% as 3/4 and finally 88-100% as 4/4


Weight and lawn

ADD 2019-09-21: The additional weight of this model, has the side effect of making more visible tracks in the lawn. It is not permanent wear track, nor the slight tracks visible in the dew if started in the morning, as with the previous models. Have a look at this autumn image:

It looks a bit like the snow near a mountain hotel.

That was not an effect I had imagined, so I guess the tires ought to have been wider to better distribute the weight.


Error examples

This is a typical example where it reports a collision error it has brought upon itself….

Update 2020-04-29: It has clearly been improved by software, have only seen this once this season yet.

See suggestion below on how to easily fix that with a changed piece of plastic….


And another example from the other side of the same Rhododendron 2020-07-21, where it managed it self to get squeezed in – that never happened with any of the simpler models, but is not the first tine for the 435X.


Odd bugs in spring 202o, fixed under warranty

Update 2020-04-29:

I had a few odd bugs with it after the return from winter service, and they actually did some hardware changes to fix them.

The first was that it would not pair with the docking at all, and here the solution – odd as it may sound – was that they on Husqvarna’s request swapped the battery pack(!)
Something in the new software was incompatible with the circuitry of the original battery…

Getting back it worked but after a while it started randomly claiming that it bumped into something on plain field. And sometimes so much it ended in a “Collision error”.
They tried to find the bug, and ended up, on Husqvarna’s request, swapping ALL the five sensor boards with new ones as the software stupidly does not log which one that triggers an event…

So right now I’m glad for the warranty, and hope the bug frequency fall before the warranty runs out…

Update 2020-04-30:

A few weeks ago I extended the lawn somewhat and was a bit sloppy burring the cable, so today it caught and cut it. Nothing odd about that. BUT the app did not give me a notification on it!! By pure luck it was in plain view through the window from my desk, and I noticed  it not moving/mowing. Opening the app did display a “No loop” message, but why on earth they don’t think that is worth a notification is beyond me….


New bug September 2020

I have just had a new bug this morning. In the app it is just showing “Mowing”. They OUGHT to be able to find out after a few minutes that if the GPS location is not changing beyond the accuracy, then it must be stuck….

The blade-disc is clearly blocked too.


Possible improvements

Apart from the suggestions from the previous models, and the above mentioned software stuff.

The rear INWARDS ‘fender’ (afaik 591 46 78-01) could be improved by changing it from FLAT  to an ARC. That would mean that it could practically always rotate the rear part reducing the risk of it getting confused on small trees or the like in the lawn close to the boundary wire. I have tried to add it in green here

I have had it getting itself caught not being able to rotate the rear part about a handful of times the last month.


User modification

I have last night [primo August 2019] modified it by adding a top protective shield to the cosmetic click on front top cover.

So I now have to pull one end of the handle up to stop, rather than pushing the now inaccessible end down.

It can still be carried (horizontally or vertically), and I hope it fixes the branch issue. If it works, I might redo it in a better material (this is cut from the lid of a broken storage box… This plastic is a bit brittle so I fear a branch might crack it – time will tell.

Of course it will still be able to get caught by a branch when going rear end first, but it is not worse off than the original.

Should you need to access the horrible jogwheel, you can just click off the top cover with the protective shield.

Off course optimally they should change the top cover design to some ‘hinged’ design, like they had on the 230ACX more than a decade ago(!)

Update 2020-05-30: The above DIY fix has worked really well for months, and has practically eliminated the problem, I now see it less than once a fortnight, only seen it trice this season..
Update 2020-07-23: It still works well, but the material I used was not optimal, and begins to crack, so will need to find something better soon. Preferably both shapable and transparent. Maybe I just find a suitable sheet of metal, end forgets about the display…


Blades and screws

The blades and screws are slightly changed, though the old type of blades can be used.

Changing the ones it came with I used some of my old ones, before I realised the screws had changed, not threaded all the way. So they went smoothly in for the first part, but firm the rest – now I know why (New types to the right):

The new original blades are also slightly different, the sharp edge is indented at the rear part of the blades, and has two small dents at the front.