2016 Mercruiser 6.2 ECT - long beep every few minutes???

[tpenfield]

I survived the dentist and PT appointments and will be back at the boat tomorrow. Plan for the day is . . .

1) Try some new fuses
2) Check resistance to battery ground for the 3 ground pins on the connector(s)
3) See if I can verify that the Pin 'A4' stays at battery voltage with the PCM powered.
4) Maybe swap out the battery.

I also think I should upgrade the VesselView to the latest patch level, while I got 'the hood up'.

 

[tpenfield]

Quick Update . . .

I not able to verify the ground at the pins . . . need to check the wiring diagram a bit more.

I did verify 0 ohms from the ground cluster at the back of the engine to the battery '-' terminal . . . so not a ground strap corrosion issue.

I did find the buzzer . . . 3 of them. The one making all the noise was buried under a bunch or harnesses. . hardest one to reach.

I put tape on the buzzers to squelch the noise a bit.

Also got an 822/16 fault on the starboard engine . . . which is open/short on an O2 sensor. I cleared it and re-checked the connections to the sensors. I'll see if it comes back.

 

[tpenfield]

Another update . . .

I spent some more time checking things on the engines.

I was able to verify that the voltage on the BATT pin ( C-Pocket, Pin A4) is within 0.25 volts of the battery voltage while the system is powered up (i.e. ignition on). The PCM 'sees' the battery voltage as a little less and the VesselView 'sees' it even lower.

Once in a while the system will start up OK and other times it will give the 'critical' voltage warning. lt seems like an erroneous warning on the VesselView's part, since none of the voltages are at a 'critical' low state.

The entire system seems like a hodge-podge of stuff . . . Smartcraft, Vessel View, Axius, Guardian. Not sure if they are all separate systems or just marketing fluff.

 

[alldodge]

Can we say that while running the ALT is putting out 14.5V but the PCM does not see that level?

 

[tpenfield]

We cannot. The Alt's are putting out 14+ volts and everything follows. If just on the solar power, the batteries are at 13.7 and the voltage to the PCM is within 0.25 volts. With ignition on . . . the batteries are in the 12.7-12.9 range and voltage at the PCM's are 12.5

 

[alldodge]

Sorry Ted, I'm not connecting, guess just getting to old.

There is 14+ at the Bat's when running, but it screen pics of Diacom it shows no more then 13.1. For me that is a big issue

 

[tpenfield]

Sorry Ted, I'm not connecting, guess just getting to old.

There is 14+ at the Bat's when running, but it screen pics of Diacom it shows no more then 13.1. For me that is a big issue

When the engines are running the VesselView screens show 14 volts. Here is a picture while heading out of the harbor. Not sure if I have posted it previously.
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I am more comfortable that the voltages are adequate, seeing such on the Diacom screens. Just not sure why VesselView does not like it.

 

[alldodge]

Not sure you posted it either, Tx
Ya know, if my meter was showing 13.9 to 14V and not closer to 14.5 I would be taking measurements at the ALT and Bat's to verify my ALT was doing what it should.

If output was correct and VV was showing the above, then that would be my next look as to why. Who knows maybe its VV that has the problem

 

[tpenfield]

Not sure you posted it either, Tx
Ya know, if my meter was showing 13.9 to 14V and not closer to 14.5 I would be taking measurements at the ALT and Bat's to verify my ALT was doing what it should.

If output was correct and VV was showing the above, then that would be my next look as to why. Who knows maybe its VV that has the problem

Yes, VesselView seems to be the problem. I noticed there is a ECM-like module under the dash panel that all sorts of wiring connects to. Maybe there is an issue up at the helm rather than the engine.

The wiring is a rats nest. So maybe something at the helm has a bad connection.

I’m still figuring out how all this tech stuff plays together. My head is starting to hurt.

Another thing- I can plug the Diacom OBD- M connector right to the engine and get some data. . . Or . . . I can connect the Mercruiser CAN adapter and plug into the port at the helm and get more data. The fault code history was different between the 2 connections. A real head scratcher

 

[alldodge]

If you ask really, really, REALLY nice maybe @muc might comment

 

[Scott Danforth]

Yes, VesselView seems to be the problem. I noticed there is a ECM-like module under the dash panel that all sorts of wiring connects to. Maybe there is an issue up at the helm rather than the engine.

The wiring is a rats nest. So maybe something at the helm has a bad connection.

I’m still figuring out how all this tech stuff plays together. My head is starting to hurt.

Another thing- I can plug the Diacom OBD- M connector right to the engine and get some data. . . Or . . . I can connect the Mercruiser CAN adapter and plug into the port at the helm and get more data. The fault code history was different between the 2 connections. A real head scratcher

Mongo like carburetor......

 

[alldodge]

I am Groot

 

[tpenfield]

Yes, I think it is a VV thing not an engine thing.

 

[tpenfield]

Mongo like carburetor......

Candy-gram for Mongo !

 

[tpenfield]

If you ask really, really, REALLY nice maybe @muc might comment

Yes he might

 

[muc]

I’ve been following along and trying to craft a reply, but every time I start typing something comes up.

Here are a couple of thoughts. As near as I can tell the helm has two power supplies running up to it. I don’t have access to the complete wiring diagram so it’s tough to be sure. But the first thing I see is no clean power connections on the engine batteries. The clean power needs to be connected straight to the correct battery per MerCruiser. It then feeds some stuff on the engine and also has 2 dedicated wires in the main data harnesses going to the helm. I’m guessing there is a problem somewhere in this circuit. Your voltages on the Diacom are much lower than I normally see. But I have rarely used Diacom on Mercury products. Mercury wants us to use G3 on their engines.

I will try to find the time to write up an explanation on why you’re seeing some of the stuff that you have questions about.

If I was the tech on this issue, the first place I would look is the clean power connections. From what I’ve read so far in this post. You have a low voltage issue at the helm. It sounds like it is getting worse. There is a possibility you could loose steering control.

 

[tpenfield]

Thanks @muc for your insights, they are very helpful.

I'll start checking the voltages at the helm. I agree that there are a couple of voltage sources and they are off by more than they should be, so something is not right with the power sources.

Loosing steering would be a bad thing. I guess I'd have to shut down at that point and hope for a re-start.

For the fuses at the engine (3 fuse banks) I removed each fuse, visually inspected it and re-installed them . . . no difference in the warning.

The G3 system is a bit out of my boat budget range, and I already had the Diacom from my previous boat.

It is interesting that I can connect the computer at the engine and get a limited set of data, or connect at the helm and get the more extended set. Also can choose which engine via the helm connection.

FWIW - here is a screen shot connecting directly to the engine. I see that the 'ignition switch voltage' is higher than the 'battery voltage' by about 1.1 volts.
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But with the engine running, these voltages do see low.

I'm also wondering if the helm is being fed from the accessory battery, while the engines are being fed from their own batteries. This may be the clean power issue that you speak of, since there would not be a single source of power. I've read in a few places that the PCM wants a single 'clean' source of power.

There are 4 battery banks . . .
Starboard Engine (1 Battery)
Accessories (1 Battery)
Port Engine (1 Battery)
Inverter (4 Batteries)

They all share the same ground (from what I can tell by the wiring).

 

[tpenfield]

Thinking 'out loud' here. . .

If . . . (and it would not surprise me at all, based on the wiring design of this boat) . . . if the helm (and portions of the overall engine systems) were getting power from the accessory battery and the engines getting their power from their respective engine batteries, the power issue would make sense, since the accessory battery seems to be the weaker of the batteries . . . and it is not charged as much from the solar charger.

1) When I had the boat in my driveway on shore power all the batteries were being charged in a fairly equal fashion, I did not get the warnings.

2) Once in the water, and even before my solar charger, I was getting the warning, since the accessory battery is used more than the other batteries and would be sitting at a lower level. I'm also thinking maybe the Accessory Battery may be on its way out.

Anyway, I can run a few basic tests to see where the voltages are coming from. I am wondering, as a short-term solution, If I tie the Accessory Battery and the starboard engine battery together if that would be a good idea or at least reveal the issue to a greater extent?

 

[dingbat]

Thanks @muc for your insights, they are very helpful.

I'll start checking the voltages at the helm. I agree that there are a couple of voltage sources and they are off by more than they should be, so something is not right with the power sources.

Loosing steering would be a bad thing. I guess I'd have to shut down at that point and hope for a re-start.

For the fuses at the engine (3 fuse banks) I removed each fuse, visually inspected it and re-installed them . . . no difference in the warning.

The G3 system is a bit out of my boat budget range, and I already had the Diacom from my previous boat.

It is interesting that I can connect the computer at the engine and get a limited set of data, or connect at the helm and get the more extended set. Also can choose which engine via the helm connection.

FWIW - here is a screen shot connecting directly to the engine. I see that the 'ignition switch voltage' is higher than the 'battery voltage' by about 1.1 volts.
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View attachment 366756
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But with the engine running, these voltages do see low.

I'm also wondering if the helm is being fed from the accessory battery, while the engines are being fed from their own batteries. This may be the clean power issue that you speak of, since there would not be a single source of power. I've read in a few places that the PCM wants a single 'clean' source of power.

There are 4 battery banks . . .
Starboard Engine (1 Battery)
Accessories (1 Battery)
Port Engine (1 Battery)
Inverter (4 Batteries)

They all share the same ground (from what I can tell by the wiring).

Never assume anything.

The should be a ground cable/strap between all four batteries. I didn’t see any in your pictures.

As it stands you have 3 different computers hooked up to 4 different ground teference /potentials

 

[tpenfield]

Never assume anything.

The should be a ground cable/strap between all four batteries. I didn’t see any in your pictures.

As it stands you have 3 different computers hooked up to 4 different ground reference /potentials

No, all seven batteries '-' terminals are connected together with very thick cable (Yellow). It is just hard to see in the pictures. I will double check so as to eliminate possibilities.

I am learning the wiring convention is this boat. . .

Red = Power source voltage
Gray = Switched Power (i.e. lights accessories, etc)
Yellow - Ground

One nice thing is that all wires are individually marked along their entire length with a reference number and brief description, so you can more easily trace the wiring over the length of the runs.

Cruisers Yacht also send me the harness & connector drawings, so I have begun to look at those to see if the engine systems are getting multiple power sources.