255XE Errors

[corvettemina]

I have a 2023 255X that is giving me issues 90% of the time. I am getting BCU communication error, Port engine communication error, starboard engine communication error, GPS error. The errors don’t go away and happen every time. When I drive the boat, it gets to WOT but doesn’t stay there, and the RPMs bounce up and down and the boat bogs down intermittently. And when driving it thinks its in float mode then comes back to running mode. Its extremely annoying cause the buzzer comes on and off almost the whole time i take the boat out. The batteries are at 12.6 volts before starting and are always plugged in to a charger when not in use. I also disconnected the rear stereo controls to see if that was broken and it bringing the CAN network down but that didn’t solve it. I also looked for any broken and separated CAN lines but didn’t see anything. Everything mechanically seems to work so i'm assuming its electrical. I've unplugged and re plugged everything on the CAN network i could find. I've cycled the key a bunch. checked grounds on the battery. unplugged and re plugged the screen. Just want to see if there's anything else i can do before i take it to the dealer.

 

[sgust]

With so many loss of communication errors, I'd say its a common ground circuit or common power circuit that feeds the modules. You can check terminal tension in connectors pretty easily by giving the circuit wires going into connectors a little pull and see if something backs out. If its an issue with terminal retention, it will push that terminal out slightly causing issues you're describing. Otherwise if you can find schematics, a voltage drop test will most likely find your issue.

 

[TommyMcK]

I had a host of BCU error issues initially with my 2023 222XD. I found that the nuts on the bus bar (both positive and ground) were loose. Tightening them up fixed everything immediately. There are, evidently, a variety of things that can cause BCU errors, but it seems that a non-inconsequential percentage of problems that folks report are associated with loose electrical connection issues.

The bus bars on the 222XD is in the engine compartment at the bulkhead that separates the engine compartment from the battery box. It may be someplace else on the 252s. It's a quick check in any case.

 

[DSG!]

My 10 hour, 275 SDX 2023 has developed a stop BCU fault. Both engines will start, but the code will be generated, and the throttle does not work on the starboard Engine. I’ve done the multiple power off and start procedure without effect. I replaced the start battery even though it was charging normally. One oddity may be that when I first turn on the ignition, both batteries display 11.5 V and then will increase to 12.9 within about 30 seconds. I don’t know if this is a new or old phenomenon. Turning off the batteries clears the code, but it quickly reappears in about one minute regardless of whether the engines are running or not.

Is there a YDS kit available for this year and model? Has anyone had this situation?

 

[TommyMcK]

My 10 hour, 275 SDX 2023 has developed a stop BCU fault. Both engines will start, but the code will be generated, and the throttle does not work on the starboard Engine. I’ve done the multiple power off and start procedure without effect. I replaced the start battery even though it was charging normally. One oddity may be that when I first turn on the ignition, both batteries display 11.5 V and then will increase to 12.9 within about 30 seconds. I don’t know if this is a new or old phenomenon. Turning off the batteries clears the code, but it quickly reappears in about one minute regardless of whether the engines are running or not.

Is there a YDS kit available for this year and model? Has anyone had this situation?

Regarding the battery display, that's normal prior to start. When you first turn on the ignition the engines (before starting), there are a bunch of startup items that get executed that draw current. The voltage at the output terminals of a battery is a function of current draw, and when there is significant current draw the voltage drops. The readings that you are seeing is typical. I've never been quite sure what is actually drawing that initial current because even with the blower on, the reading comes up after about 30 seconds or so as you note. In my case, the house battery usually drops farther than the start battery when the ignition is first turned on prior to starting the engines.

I don't have much in the way of your BCU error other than what I noted above, which is to check all of the terminal blocks in the engine compartment to make sure everything is tight.

 

[steelhorse454]

Remember also, many of these connect screens are faulty. Just had mine replaced under warranty on my 2023 boat.

 

[DSG!]

My 10 hour, 275 SDX 2023 has developed a stop BCU fault. Both engines will start, but the code will be generated, and the throttle does not work on the starboard Engine. I’ve done the multiple power off and start procedure without effect. I replaced the start battery even though it was charging normally. One oddity may be that when I first turn on the ignition, both batteries display 11.5 V and then will increase to 12.9 within about 30 seconds. I don’t know if this is a new or old phenomenon. Turning off the batteries clears the code, but it quickly reappears in about one minute regardless of whether the engines are running or not.

Is there a YDS kit available for this year and model? Has anyone had this situation?

So, i bought the diagnostic tool, which allowed me to determine the problem. I also purchased a service manual. However, afterwards, I decided to try a ChatGPT query using the appropriate keywords. And immediately it returned an accurate assessment, which I clearly should’ve done in the first place. I recommend using this tool to instantly assimilate information from everywhere.

 

[TommyMcK]

So, i bought the diagnostic tool, View attachment 232619which allowed me to determine the problem. I also purchased a service manual. However, afterwards, I decided to try a ChatGPT query using the appropriate keywords. And immediately it returned an accurate assessment, which I clearly should’ve done in the first place. I recommend using this tool to instantly assimilate information from everywhere.

So what was the issue in your case?

 

[DSG!]

My BCU issue ended up being my batteries, although only 20 months old and testing “Good”, had just enough current drop under load to trigger the fault. Replacing just the start battery did not solve the issue, but replacing both did!

 

[sbeassie]

Had the BCU Stop error come up for the first time Sunday. Was back at the marina about to load the boat onto the trailer. Tied up and shut down both engines with the start/stop buttons. This is when the error appeared. Had both throttles in neutral when I shut down. I had just used reverse to keep from bumping into the dock. I went and backed the trailer in. I did not turn off the key or the battery switches at this point. I restarted both engines. Only the starboard engine would respond to the throttle. I loaded the boat onto the trailer with the starboard engine. I then shut down both engines and turned off the key and both battery switches. After a few seconds I turned both battery switches and the key back on. The error cleared. I didn't try to restart the engines. Hopefully this is a rare occurrence. I will check all the electrical connections.

 

[anmut]

Had the BCU Stop error come up for the first time Sunday. Was back at the marina about to load the boat onto the trailer. Tied up and shut down both engines with the start/stop buttons. This is when the error appeared. Had both throttles in neutral when I shut down. I had just used reverse to keep from bumping into the dock. I went and backed the trailer in. I did not turn off the key or the battery switches at this point. I restarted both engines. Only the starboard engine would respond to the throttle. I loaded the boat onto the trailer with the starboard engine. I then shut down both engines and turned off the key and both battery switches. After a few seconds I turned both battery switches and the key back on. The error cleared. I didn't try to restart the engines. Hopefully this is a rare occurrence. I will check all the electrical connections.

If you search this forum, I believe there's an issue reported where you might get that error if you are using reverse with the wheel turned and then shut off the engine.

 

[FSH 210 Sport]

Had the BCU Stop error come up for the first time Sunday. Was back at the marina about to load the boat onto the trailer. Tied up and shut down both engines with the start/stop buttons. This is when the error appeared. Had both throttles in neutral when I shut down. I had just used reverse to keep from bumping into the dock. I went and backed the trailer in. I did not turn off the key or the battery switches at this point. I restarted both engines. Only the starboard engine would respond to the throttle. I loaded the boat onto the trailer with the starboard engine. I then shut down both engines and turned off the key and both battery switches. After a few seconds I turned both battery switches and the key back on. The error cleared. I didn't try to restart the engines. Hopefully this is a rare occurrence. I will check all the electrical connections.

I think these systems are sensitive to low voltage transients. Checking all the electrical connections seems to be the best first step, I’ve seen multiple posts about people finding loose connections on a buss bar.

I’m going to assume that you have an onboard charger and keep the boat plugged in when not in use, and that the DVSR is functioning normally?

 

[sbeassie]

I think these systems are sensitive to low voltage transients. Checking all the electrical connections seems to be the best first step, I’ve seen multiple posts about people finding loose connections on a buss bar.

I’m going to assume that you have an onboard charger and keep the boat plugged in when not in use, and that the DVSR is functioning normally?

Yes and yes.

 

[sbeassie]

If you search this forum, I believe there's an issue reported where you might get that error if you are using reverse with the wheel turned and then shut off the engine.

I read some of those threads as well.

 

[DSG!]

On the drive X models, a stop BCU error, where one engine will start, but not respond to throttle, and the other engine is OK is often due to a mechanical shift gate issue. The on board diagnostics on the MFD will show a BCU fault 184 and no engine errors.

this assumes all the common issues, such as weak batteries, loose connectors, or other general electrical problems are not present. After doing extensive diagnostics on my 275 SDX, I found this error will usually clear with wiggling the shift gates and being sure there is no obstruction or foreign material inhibiting shift gate motion. The slightest inhibition of shift gate motion may generate a Stop Bcu fault. Later models with shift gate actuators instead of shift cables may be addressed by pulling the pin in the actuator – lever arm, which allows manual motion of the shift gate. this procedure will be in the users manual.

It may also be a good idea to cycle both engines through forward and reverse during the flushing procedure, but always shut down in neutral, with the helm straight ahead. Having a abnormal comtrol position during shut down, may confuse the BCU.

You may find that posting this question to ChatGPT AI may give you other additional information.

 

[sbeassie]

On the drive X models, a stop BCU error, where one engine will start, but not respond to throttle, and the other engine is OK is often due to a mechanical shift gate issue. The on board diagnostics on the MFD will show a BCU fault 184 and no engine errors.

this assumes all the common issues, such as weak batteries, loose connectors, or other general electrical problems are not present. After doing extensive diagnostics on my 275 SDX, I found this error will usually clear with wiggling the shift gates and being sure there is no obstruction or foreign material inhibiting shift gate motion. The slightest inhibition of shift gate motion may generate a Stop Bcu fault. Later models with shift gate actuators instead of shift cables may be addressed by pulling the pin in the actuator – lever arm, which allows manual motion of the shift gate. this procedure will be in the users manual.

It may also be a good idea to cycle both engines through forward and reverse during the flushing procedure, but always shut down in neutral, with the helm straight ahead. Having a abnormal comtrol position during shut down, may confuse the BCU.

You may find that posting this question to ChatGPT AI may give you other additional information.

Thanks for the information!