Zero Off Flashing 70 MPH and Speed Changes on 2017 ProStar

[BlueSki]

Has anyone had issues with Zero Off changing to speeds that are outside of normal, specifically 70 mph and 50 mph? This happens when sitting idle and fortunately not to this degree when under power, otherwise we would have some entertaining video. We have had it change to 36 as we enter the course when someone is expecting something slower like 26 or 28 and the driver has to quickly change it back. Also fortunately, this does not happen once the boat is up to speed and ZO takes over.

When the speed changes to 70 or 50, the speed setting may quickly flash back and forth from a normal speed setting to these or it may simply lock and ZO will not respond to attempts to change the speed setting. We cannot select these high speeds, ZO makes the change on its own. Doing a full shutdown of the boat and killing the main power switch helps, but does not always work.

This is on a 2017 ProStar running Rev R on a single puck. Yes, we contacted ZO and they said it was the display or display software.

[chrislandy]

I've had my 2015 act similarly this year, but it has always coincided with really bright & hot days, so presumed the screen overheats in the sun and gets some ghost touches (for mine it's usually the speed up and pull type areas that get the ghosting)

[Mastercrafter]

Given the piss-poor reputation of those displays, I'm not too surprised to read this, however that seems more like a software issue than a touch-screen failure, since its going outside of regular parameters. Typically the touch-screen ghosting causes random speed changes as if the driver is touching the screen, but it will never go over 36.

Check your connections on the back of the screen, perhaps take to dealer for a software reflash. I'm told old batteries with bad cells can cause weird issues too. Maybe worth a new battery to eliminate a possible variable.

Different issues but... with dual pucks on a cloudy day I've had ZO display 70+ mph while at speed, through the course, therefore all but killing the engine and coming to a stop. Waited a few, next pass, displayed 0 mph through the course, and the boat took off, WOT. Nice, real nice.

[BlueSki]

@Mastercrafter, I was thinking the same thing about software. The boat has a bimini top, so the screen avoids direct sunlight. The boat is a collegiate team’s boat, so hopefully the fix is as simple as a software update.

[jpwhit]

I've taken apart and experimented with both display and the ZO display-less head unit. When you power up the display w/o the ZO head unit connected, you get behavior a little like you're seeing. So I can't say with certainty what is wrong, but I think it's most likely an issue with the ZO head unit mounted in the firewall under the dash. It's a black round 5" unit. It looks like a ZO gauge w/o a display, because that's actually what it is. Either that or an issue with the CANBUS wiring between the two.

The display units are extremely well sealed from water penetration. But the ZO display-less head units are not that well sealed. And I've heard of them failing on the ProStar due to water intrusion. I would take yours out and look inside for water. The 7" displays have some problems with the LCD and touchscreen, but otherwise are very reliable. And this isn't an issue with the LCD or touchscreen on the display unit.

[BlueSki]

@jpwhit that is very helpful, thank you.

[jpwhit]

To add a little more detail. When I say to open up the ZO head unit and check for water. That could range from there being actual wetness inside the unit, to being signs of water marks or corrosion on the circuit board. Check both sides of the circuit board.

If the circuit boat looks fine, then it still could be an issue with the head unit, but moisture is the most common cause of issues with the head unit.

Since this may be a communications error between the two units, it also couldn't hurt to unplug and re-seat the connectors on both the Murphy display and ZO head unit. It's actually the same 23pin connector on both. The Display has 2 of them, a black one and a gray one. The connections for the CANBUS are in the black connector on the display. No need to do anything with the gray connector. The ZO head unit has a single 23 pin connector that you'll have to disconnect anyway to take that out and open it up to check for signs of moisture or corrosion.

Another thing that would be interesting to try, when it's acting up and displaying 50 or 70mph. What happens if you drive through the course w/o a skier. Does it lock into a speed? If so, was it the last speed that was set?

The speed control system is completely controlled by the ZO head unit. The boat display is only a "remote terminal" that can read and send settings to the ZO head unit. I've never actually tried this, but if you had the front panel from the original style ZO gauge that has a small LCD and four buttons, I'm pretty sure you could plug it into the ZO head unit PCB. Then that would also be a another "terminal" to see and change the ZO settings.

If the PCB looks fine, and un-plugging and re-plugging the connectors doesn't help. Then this is going to be tricky to diagnose. If the boat is still in warranty, I would get it in quick to get it on the record that something is wrong and needs to be fixed.

[BlueSki]

@jpwhit thanks again. I let the team president know. He had to take the boat in for a starter issue so he is having them check into this as well.

[lefty]

Reviving an older thread as this is happening to our 2020 PS, among other odd issues with zo. @BlueSki how did this get resolved?

[Jody_Seal]

un plug the reciever and see if it will run correctly in rpm mode.

 

[lefty]

Is the gps puck the same as the receiver?

[liquid d]

soooo...what could you run at 70?

[BlueSki]

There was nothing wrong with ZO, it was actually the ProStar’s screen unit, so it was a MasterCraft problem. New screen and the problem was fixed. 

[jpwhit]

What are the “other odd issues”?

[lefty]

1.was unable to turn off course manager yesterday. Had to delete the course it was reading.  Seemed that although zo was engaged it wouldn’t hold set speed.  Between skiers yesterday iset speed was flashing in and out at 70mph and back to actual set speed.  Eventually by turning course manger off seemed to be ok.

2.when starting the boat today it did not run through a normal booting, no beep etc.  read 0 satellites and would not engage any profiles.  Would not read any speed or rpm or voltage etc. Heading back to dock it appeared as if the 3 analog gauges also went down.

3. Eventually kinda engaged a skier profile but would not hold speed even though the mph went from white to green.  Analog gauges came back up.

4.docked boat, killed battery master switch, did some research, went back to boat and fired it up and everything seemed normal, booted normally, 14 satellites found and was able to manipulate profiles etc. did not find any errors or faults in diagnostic screen.

Tomorrow I will check the connections for corrosion and damp.  It is a bit cool here still so it may be a moisture issue.  Sometimes condensation inside the boat in the morning.   I also under stand that a weak battery may cause problems and I am due for a new battery end of this season so may just do that now.

[BlueSki]

@liquid d Ha! It depends on how they managed the slack line. In reality, a skier usually did fine because it started at 70 and the dropped to something low on the display.

[jpwhit]

The screen reads RPM and Voltages directly from the engine ECM. Along with the screen not booting up properly, it sounds like your screen is having problems. Hopefully the boat is still under warranty. If not, I do repair these screens when I have parts available. Parts for these screens are hard to come by. If you want to go that route, send me a PM. Its a whole lot cheaper than buying a new screen.

[lefty]

Thanks @jpwhit, follows what happened with @BlueSki situation by the sounds of it. Hopefully I can get this covered under warranty, if not I will reach out 

[lefty]

Hey @jpwhit, so swapped out battery and looked for obvious connection issues. Started boat, again no booting and no readings on screen nor on analog gauges. I find the analog gauge issue confusing. Are they downstream from the ZO screen or independent, how are they related? Still planning on a trip to the dealer of course

[jpwhit]

That's not actually an analog gauge. It's a digital gauge that the screen controls. So the screen reads data from the engine ECM and fuel level sensor and it "talks" to that gauge and tells it what to display. Or if you have "fuel management" turned on, the screen uses a combination of the fuel level sensor data and the fuel management data to control what reading is sent to the fuel gauge. 

I think your ZO is probably fine. I think your screen is flaking out. Actually the computer board in the screen. 

[lefty]

Thank you sir! At the very least I am learning about new things through this process, whelp off to the dealership after the long weekend. Out of curiosity, anyone know  what this screen part is worth off warranty? 

[ETskier]

Sad thing is these screens are not going to be well supported in the aftermarket and then only at great expense. 

[Mastercrafter]

4 hours ago, lefty said:

Thank you sir! At the very least I am learning about new things through this process, whelp off to the dealership after the long weekend. Out of curiosity, anyone know  what this screen part is worth off warranty? 

Unfortunately they’re not cheap. Great Lakes Skipper had some NOS screens on eBay for $3400 a while back but now this is the cheapest at $4300. Dealer is closer to $4800 I believe. 

https://www.ebay.com/itm/404415479384?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=PPsq0eSBQmO&sssrc=4429486&ssuid=a-9NW19sQAi&var=&widget_ver=artemis&media=COPY

 

a dealer  

[chrislandy]

Would it be worth reinstalling the firmware incase something has gone askew? 

[jpwhit]

57 minutes ago, chrislandy said:

Would it be worth reinstalling the firmware incase something has gone askew? 

I would recommend against that, at least until the dealer has looked at it to determine if there is warranty coverage. Or let the dealer try that. A lot of times when the screens start to act flaky, updating the firmware will end up making them bricked. 

Just finished fixing one from a Nautique 200 yesterday where that happened. 

@lefty when the screen doesn't boot, what happens exactly? Nothing on the screen at all? Does it say "Booting..." on the top left of the screen, but never goes beyond that? If there is nothing on the screen, do the button backlights come on for about 2 seconds, go off for a second, then then come back on?

[lefty]

It’s intermittent still, just tried 3 times and all 2 of 3 it came up normally was reading satellites and I was able to manipulate ZO settings. Stayed on dock but assume it would have run normally as well.
The other time the gauge screen did come up, just the data was either reading 0 or some number that made no sense.  Usually flicking around random numbers and ending up at 0.  After 10 secs of that all gauges read correctly. Also got the low fuel note in top left, visually there is 1/2 a tank ., then that disappeared as well. Other 3gauges came up normally all 3 times today. 

when it is not coming up, it does say booting on top left. no beep. Screen comes on in normal orientation etc but all readings are 0s. 
FWIW, I have had overheating errors that are not cancelled out as I haven’t had it to a dealer since they came on.  The errors are legit and was aided in sourcing their cause and remedy on BOS last summer. Tried last fall to get it looked at but it’s a long story regarding the “master craft shop”that I went to that had no ability to plug in the boat to the correct diagnostic tool. Will be taking it elsewhere this time.

Ok seems I won’t be getting much work done today lol. Back into boat and scrolled diagnostics, found there is a 3 event fault now as well as the uncleared high temp warnings. Am feeling not so smart as I didn’t notice this yesterday.somewhat certain it is not older than a week   See attached. 

[jpwhit]

The problem may not be the screen itself or the zero off. Based on your description and that error. You may have a intermittent CANBUS wiring problem. Here's a labeled picture of the HV700 Screen wiring harness. Unfortunately, half of the screen harness is under the dash and the other half goes behind the right side panel where the throttle lever is mounted. So it's a little bit of a pain to get to all of it. 

Those inline CANBUS splices could be a trouble spot worth checking. I've also seen pins in any of the connectors come unlocked from the connector housing and get pushed out the back so they are barely touching the corresponding contact in the mating connector. 

 

[lefty]

On e again thank you for sharing your time and expertise. Once I get under the dash and get my bearings I will in all likelihood have more questions. 
Fingers crossed that I can find an issue without making it worse lol

[jpwhit]

If you mess with the wiring harness and it completely quits, then it'll be easier to find the problem 😉

You may find it easier to take the screen out to give you good access. 

Remove the black and gray large 23 pin connector on the back of the screen by reaching up under the dash. There is a clip on each one you can lift the latch with your fingernail. The waterproof seals get a little stuck when they haven't been off in a while. Wiggle the connectors until they break free. 

The screen is held in by aluminum clips on threaded studs. When you first look at it under the dash, you'll probably say to yourself two of the clips look pretty easy, the third is a little tight but manageable, and there's no way I can get the fourth one on the far corner. Well, the good news --- there isn't a fourth one, there are only 3 clips. If you take the 2 clips off the side nearest the steering wheel, and just loosen the nut on the 3rd one some. You can shift the screen a little to the right, away from the steering wheel, and pull out the side closest to the steering well. Then you can shift it left to get the other side out. 

First thing I'd do is examine all the contacts in the black 23 pin plug and socket. Make sure none of the contacts are pushed back in the connectors. Then do the same for the connector going to the boat wiring harness. In both of those pay close attention to the two CANBUS wires. 

You can also plug the screen back in and start the boat. I'd try watching the engine RPM in the hope that it jumps around enough that you can tell if it stops updating. And then wiggle stuff to see if you can find a bad connection. 

When you put the screen back in, don't tighten the nuts on the clips any more than needed for the screen to not shift around. Putting uneven pressure on the case of the screen can cause touch screen false readings. 

[lefty]

Awesome advice, thanks again.  Before I read it I had already taken the side panel off.  Unplugged the 23 pin from the screen and looked and connectors, nothing obvious to the untrained eye.  isolated the can bus wires from the rest, to get a good look at the union connection.  Thought I had it figured out as one zip tie was right at the joints, bending them, and so I straightened it all out and fired up the system.  Did it about 4 times and everything booted and looked perfect.  Left it on, zero off was on to a known profile.  Ran the blower while tidying up my mess thinking I would fire the engine and go for a spin.  After about 3-4 minutes of the blower running things went south , flickering readings, pm reads 0, no satts, low fuel, set speed went to 70 and back and forth etc.  Hand my hand under the dash and was manipulating the can bus in-line connection to no avail.

tomorrow I will take the screen out and look closer at the pin connectors, maybe I will post a picture

 

[Andre]

That post is gold for all newer MC owners IMO. 

[jpwhit]

Just a few thoughts. Watch to make sure your battery voltage isn't dropping low. Also, blowers are electrically very noisy. Do you leave it running all the time? I know some people do. If so, test with it off to make sure it's not causing CANBUS interference. Make sure that yellow CANBUS terminator is there. Because if it's not, or it's not right, the CANBUS will be super susceptible to electrical noise. In you have a volt / ohm meter. Unplug the yellow terminator and set the meter to ohms. Touch the 2 meter leads to the 2 terminal in the yellow terminator. Doesn't matter which meter lead goes to which pin. It should read around 120 ohms. Plus or minus 20 ohms won't make a difference. 

Hopefully it is a wiring problem, and I would think that's most likely, but it still could be the screen. If it's the screen, it would be the CANBUS driver chip in the screen is failing. 

[lefty]

My mind is blown!  Will do this tomorrow and keep everyone who’s watching updated.

Our boat has 2 blowers, one runs continuously when the engine is running in an attempt as I understand it to keep the compartment cool in this vintage. There is also the usual blower switch that clears out fumes prior to starting. I will use the open the cowling technique tomorrow instead of the blower  switch. If all is good and the screen acts up when the engine is running I’ll disconnect the other blower and see. 
 

Define “battery voltage too low” for me, I would have to put a meter on the battery to determine this I think as I can’t trust the screen reading.  I have a basic knowledge of batteries and how to test them using a meter

The screen issue has occurred during the engine running as well as at rest so unless there is another separate  issue affecting battery voltage I,m lost, as I would expect the voltage to remain fairly constant with the engine running.

[jpwhit]

Lol... I looked up the official spec for voltage input to the screen. It's 6-32V DC, so seems completely unlikely battery voltage is the problem. 

[lefty]

So far today-glassy morning. tester on battery at rest-12.6.

started boat no bilge blower on, ZO normal boot and operation. Drove my wife skiing all good. At skier change, ZO screen goes squirrelly. Unplug secondary blower and kill power at battery switch. Restart ignition and ZO still squirrelly. Turn off ZO and ski using iPhone Speedo.

return to dock and put tester on Can bus terminator. Get steady reading of 94-96 ohms. Assuming this is close enough to range?

screen pin connectors are next

[Mastercrafter]

@lefty.. where are you located? 

[lefty]

Ontario Canada

[lefty]

Following the clear instructions of @jpwhit I was able to easily remove the screen from the dash and have a look at the pin connectors.  To my untrained eye everything looks fine, nothing pushed in or loose.  All male pins looked exactly the same, clean as a whistle. Reattached screen and and went through my SOP to fire boat up.all came up normally and looked healthy. Wiggled all wires and connectors but could not recreate problems. See attached of the rpm reading, I assume this small range of reading is within the norm.
Would love to have a screen that I know works and plug it in to see what happens.  Have that needle in a haystack feeling. 

[lefty]

@Jaypro any input?

[jpwhit]

It seems like maybe there is a pattern of it working when you first start the boat, but then flaking out when the boat has been on for a certain amount of time. Do you think that's the case? If so, does it do that all the time now after the boat has been running for a certain amount of time? If that's the case, then that seems like an electronics problem either in the screen or possibly in something else attached to the CANBUS. That doesn't seem like something a wiring issue would do consistently.

I'm really surprised that bus terminator is that far off from 120 ohms, but I'm not sure that would stop it from working. Given that it's a lower resistance that it should be, it is causing the CANBUS drivers to have to work harder than normal so it's possible it's causing them to overheat. I think you should disconnect that terminator and see what happens. If you disconnect it and things immediately go south, then it's not worth continuing. Turn the master power off, disconnect it, then turn things back on and test. 

You could disconnect other stuff from the CANBUS to eliminate the possibility that something else is flaking out and dragging the bus down. Here's a link to an early post talking about disconnecting the other stuff from the bus.

https://www.ballofspray.com/forums/topic/52801-major-zo-issue/?do=findComment&comment=867566

There are also more tests of the CANBUS you can do with a meter. But we're getting to less and less likely causes now. And I don't see how the problems these tests would find would be intermittent. But it's up to you how much effort you want to put into more debugging. 

If the terminator isn't the problem, I think it's getting fairly likely it is the screen. If you want to send it to me, I can test it and fix it if it's the problem, but I'd make sure the dealer won't cover it under warranty first.

I "may" be able to throw together a test screen out of parts that work but have some defect that I could send to you to try. But I'm at the lake house at the moment and won't be back to where that stuff is until Wednesday. For example, I have an LCD touch screen that has a crack but works. I can let you know if that's an option on Wednesday. 

[lefty]

@jpwhit Thanks so much for all this. I had a ski buddy with me this morning who is way more savvy than me with machines. Seems I tested the Canbus wires but not the plug. Just did the plug and it gave almost exactly 120 ohms.

I think that my electronics skills are already maxed out, I’m more likely to cause another problem than fix the current one if I go any further. Definitely want to give the MC technician the best chance to figure this out. I can’t see why this would not be under warranty.

there has been a pattern lately of it working initially then not working, although once last week it was the opposite, didn’t work off the dock but then sorta worked at the end of 3 skiers. 
 

My plan going forward is to continue using the boat and seeing if there is a consistent pattern emerging. Also work on the dealership giving me a set amount of time to work on the boat.  Ideally this stops becoming intermittent so when I take it to them the problems are apparent. 

If you think plugging in a screen would be a solid idea to narrow it down then I would gladly accept your offer if you happen to have the right parts.   I will also see if the dealer happens to have one they could send me 

thanks again, much appreciated 

 

[jpwhit]

You actually did one of the other meter tests on the CANBUS, to measure the resistance of the bus itself without the terminator plugged in, and the reading of around 100 ohms is what I would expect. You're basically measured the terminator on the other end of the bus and some of the loads of the devices plugged into the bus. 

I think that's a good plan moving forward. I'll let you know later this week on the possibility of a test screen.