Some of my previous repairs:
www.reef2reef.com
www.reef2reef.com
www.reef2reef.com
FixReef is now also on YouTube!
https://www.youtube.com/channel/UCMAmpCr_0gSwhmTNGzXTPtg
Enjoy this repair, now in HD
And as always, uncensored, updated and corrected versions of my repair articles are a quick internet search away.
The next installment of the reef gear repair saga is about yet another very common issue with Apex. This time we are dealing with random frequent head unit (aka Apex Brain) reboots or disconnects. Typical symptoms of the problem:
- Apex head unit restarts periodically and randomly followed by
- EB832/EB8 and other modules not being able to connect to the head unit
- Disconnecting one particular modules seems to solve the problem
- Faulty module seems to power on and otherwise work just fine
In this particular repair, I have an old black Apex Display module donated to me by a fellow reefer to experiment with. His description of the problem was that the display module would cause his EB832 and other modules to randomly disconnect from the head unit. It was later determined that it was the head unit which was in fact affected by the faulty display module. Once the display was removed from Apex, everything started working again.
So let's dive right in.
On the surface, this display module does not look too bad. The main cable is a bit chewed up and Neptune's signature jumper wire is in place. But otherwise it's clean, no corrosion or any other visible damage.
As expected, it powers up and actually communicates with my test Apex head unit just fine. It can show temperature, PH and other parameters specific to my test set up. So I know that the AquaBus communication is working.
Upon closer inspection I found this component:
For those of you following my repairs, this should look very familiar. This is the old version of the CAN transceiver used by Apex to establish AquaBus communication throughout it's ecosystem. It's the 5V version of the component which was installed on all Apex Classic modules.
At first, I thought that the round blob on the surface of the component is either some flux or salt. I should know better than that by now.
A few scrapes with my pick revealed... a cavity:
That's right. There is a hole in the AquaBus transceiver of a very distinct shape and color indicating that it burned from the inside.
As usual, let's remove and replace:
Clean up the pads from old solder and replace the component:
And of course, remember to reattach the signature jumper wire. Then repair the main cable and it's time to test again:
After several hours of the module being connected to the head unit, there were no more any random resets or reboots. This display is now fixed.
But what was the actual problem and why was the display module able to communicate with the head unit if the primary component responsible for the communication had a hole in it?
That's a great question. Let's begin with the basic understanding that there is no protection between Aquabus ports and the CAN transceiver in question. Not on the data pins anyway. On top of that, we have 12v power being carried next to the data pins. So any mild short of the 12v Aquabus power and any one of the data pins will cause the transceiver to blow. Perhaps the damaged Aquabus cable caused the short, it could have also been anything else.
Also, in this particular case, the transceiver managed to function even after the short. This is fairly common as the damage was not significant enough to completely take the component out. But now, with any significant communication load, the performance of the component degrades much faster than what it was designed for. As a result, it gives in and shuts down. It is likely that this display was either corrupting the data or sending unpredictable voltage and current over the data pins causing the head unit to lose it's mind and reboot randomly.
But... this display module is now happy again
EB832 Attempting to Communicate with Apex (Bootloader Mode)
Some of my previous repairs: https://www.reef2reef.com/threads/radion-xr30-complete-no-light-repair.792711/ https://www.reef2reef.com/threads/radion-xr15-doesnt-power-on-due-to-corrosion-repair.809136/ https://www.reef2reef.com/threads/another-attempt-at-fixing-apex-eb832.804717/ And as always...
www.reef2reef.com
Another attempt at fixing Apex EB832
Some of my previous repairs: https://www.reef2reef.com/threads/radion-xr30-complete-no-light-repair.792711/ https://www.reef2reef.com/threads/radion-lights-board-level-repair.774331/ https://www.reef2reef.com/threads/ai-hydra-fan-connector-repair-significant-corrosion.793402/ First off, let me...
www.reef2reef.com
AI Hydra 26 HD Not Turning On - Prior Repair Gone Wrong
Some of my previous repairs: https://www.reef2reef.com/threads/radion-xr30-shuts-off-at-high-intensity-on-blue-channel-repair.813624/ https://www.reef2reef.com/threads/another-attempt-at-fixing-apex-eb832.804717/ https://www.reef2reef.com/threads/radion-xr30-complete-no-light-repair.792711/...
www.reef2reef.com
FixReef is now also on YouTube!
https://www.youtube.com/channel/UCMAmpCr_0gSwhmTNGzXTPtg
Enjoy this repair, now in HD
And as always, uncensored, updated and corrected versions of my repair articles are a quick internet search away.
The next installment of the reef gear repair saga is about yet another very common issue with Apex. This time we are dealing with random frequent head unit (aka Apex Brain) reboots or disconnects. Typical symptoms of the problem:
- Apex head unit restarts periodically and randomly followed by
- EB832/EB8 and other modules not being able to connect to the head unit
- Disconnecting one particular modules seems to solve the problem
- Faulty module seems to power on and otherwise work just fine
In this particular repair, I have an old black Apex Display module donated to me by a fellow reefer to experiment with. His description of the problem was that the display module would cause his EB832 and other modules to randomly disconnect from the head unit. It was later determined that it was the head unit which was in fact affected by the faulty display module. Once the display was removed from Apex, everything started working again.
So let's dive right in.
On the surface, this display module does not look too bad. The main cable is a bit chewed up and Neptune's signature jumper wire is in place. But otherwise it's clean, no corrosion or any other visible damage.
As expected, it powers up and actually communicates with my test Apex head unit just fine. It can show temperature, PH and other parameters specific to my test set up. So I know that the AquaBus communication is working.
Upon closer inspection I found this component:
For those of you following my repairs, this should look very familiar. This is the old version of the CAN transceiver used by Apex to establish AquaBus communication throughout it's ecosystem. It's the 5V version of the component which was installed on all Apex Classic modules.
At first, I thought that the round blob on the surface of the component is either some flux or salt. I should know better than that by now.
A few scrapes with my pick revealed... a cavity:
That's right. There is a hole in the AquaBus transceiver of a very distinct shape and color indicating that it burned from the inside.
As usual, let's remove and replace:
Clean up the pads from old solder and replace the component:
And of course, remember to reattach the signature jumper wire. Then repair the main cable and it's time to test again:
After several hours of the module being connected to the head unit, there were no more any random resets or reboots. This display is now fixed.
But what was the actual problem and why was the display module able to communicate with the head unit if the primary component responsible for the communication had a hole in it?
That's a great question. Let's begin with the basic understanding that there is no protection between Aquabus ports and the CAN transceiver in question. Not on the data pins anyway. On top of that, we have 12v power being carried next to the data pins. So any mild short of the 12v Aquabus power and any one of the data pins will cause the transceiver to blow. Perhaps the damaged Aquabus cable caused the short, it could have also been anything else.
Also, in this particular case, the transceiver managed to function even after the short. This is fairly common as the damage was not significant enough to completely take the component out. But now, with any significant communication load, the performance of the component degrades much faster than what it was designed for. As a result, it gives in and shuts down. It is likely that this display was either corrupting the data or sending unpredictable voltage and current over the data pins causing the head unit to lose it's mind and reboot randomly.
But... this display module is now happy again
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