2016 R7 stereo/battery/voltage issue! Help

[Ryannewcomb]

So I have been dealing with this for quite awhile now, nothing seems to help!

Stereo head unit keeps completely cutting out. It will lose power completely, then re boot and come back on. Sometimes it will flash low voltage right before shutting off. I've checked all the wires to the unit and battery, everything seems fine. Boat has done this since I purchased it in 2020, just starting to get super frustrating.

Mainly when underway with RPMS up, no issues. Same right when leaving the dock. After cruising for 15-30 mins, when pulling into a cove etc and coming off throttle, 9 out of 10 times the unit completely cuts out. This is all with the GPS unit turned off, if it's turned on, it tends to upset the radio unit even more.

I have checked batteries, all brand new this year and still doing same thing. I'm running anywhere from 13.2-13.7 volts underway, and this doesn't change when pulling off the throttle. I have tried both the "On" and the both batteries on the switch, and have the issue on either.

Factory stereo, no added tower speakers etc. Any suggestions? attached pics from this weekend

[jhnmdahl]

Rockford Fosgate says those should be good down to 10.5V, so something's wrong somewhere. I'd start by unplugging the remote (the PMX-1R in your picture) from its cable and making sure the cable connections are clean and secure, and then do the same with the remote cable and the harness attachment at the head unit.

If there are no aftermarket parts installed (e.g., a new amp on the same power line as the original hardware), I'd then trace back to fuses, the power switch, etc., and make sure wires are tight and connections are clean. Monitoring voltage at the head unit harness won't be fun, but will tell you a lot about what's really going on.

Last resort is jumping another known good 12v and ground to the receiver to see if that clears it up as being a wiring problem (most likely) or a problem with the head unit (unlikely).

John

[Ryannewcomb]

Thanks for the help John. I'm on it.

[SeattleA28]

I had the same issue a few weeks ago when I got my boat back from storage. Turned our my batteries (only one year old) were not holding a change and the low voltage message would kick on. Replaced the batteries and have not seen the message since. How long does it take for your batteries voltage to go down when just running your stereo on accessory mode?

[jhnmdahl]

Seattle makes a good point - the fact that it drops when dropping RPM suggests that it gets sufficient voltage when underway, possibly pointing to batteries. If you have a 2016 and are still on the original battery or batteries from when you got the boat, it's probably about time...

[billk2632]

Thinking the problem could be your battery switch. I assume you have checked the voltage on your batteries while sitting - first thing in the morning before cranking engines or turning anything on? They should be reading at least 12.5v and more like 13.25v if they are new. Most people don't realize that a reading of only 12v on a 12v battery is pretty much discharged and below 11v is dead. This is just a basic check, not a load test or anything like that. If they are holding voltage overnight they should be good. The Blue Sea battery switch has some circuitry in it that combines the batteries to charge them - ie while the engine is running or with a built in charger. Subsequently it isolates the batteries when discharging, this keeps you from running down both batteries with the radio for example. It does this switching based on the voltage it is reading from the batteries. And while they are nice and simple to use, these switches can have problems, mine had to be replaced last year - it quit working completely and would not turn batteries on at all. One thing you might do to test the switch theory is put the switch on combine, in this setting the switch does not read any voltages, it simply combines the batteries for charging and discharging, like the old fashion Perko 1/2/Both switch. If the problem goes away then it's the switch.

[Krob1114]

The first sign that I needed a new battery on my Mercedes actually came from the same type of warning on our radar detector..

[stifflkd]

Assuming you have the PMX-8BB tied to that remote? There is a Voltage Gauge that you can read from the display. See what it reads and compare what your battery voltage is reading on your mph gauge.

[Ryannewcomb]

Update:
I switched both batteries to new ones, just to make sure, no change

All volt meters read over 12.5 all the time, and no dipping down when the radio shuts down

I’m leaning toward it not being a battery switch issue as wouldn’t that cause other issues in the boat NL besides just the radio units? There is a 15 amp breaker for those controls that I thought about switching to a 20?

I also checked all the connections and everything seemed to be good. Thoughts? Any other next steps I’m not thinking about?

[billk2632]

I still would not rule out the battery switch, the Blue Sea switches have intelligence in them that determines which battery the house loads pull from - the good thing about them is they are simple on/off, the bad thing is you cannot manually isolate a single battery (ie when you only have one switch). All that said, have you tried running the battery switch in the "combine" position? If the problem goes away, then I would suspect the switch.

[bruceb58]

Get a multimeter and somehow attach it straight to the receiver and monitor it while driving the boat.

My bet is that its a resistive connection somewhere and you are getting a voltage drop.

I’m leaning toward it not being a battery switch issue as wouldn’t that cause other issues in the boat NL besides just the radio units? There is a 15 amp breaker for those controls that I thought about switching to a 20?

I would agree it's not the battery switch.

Do not change the circuit breaker to a 20A. A circuit breaker could possibly have high resistance but if that was the case, you replace it with another 15A breaker unless you know the wiring can tolerate a 20A breaker.

[Ryannewcomb]

No difference with switch turned to both vs just the on.

I’ll order a new switch and go ahead and try that as well. Will update in a few weeks

[billk2632]

Maybe a call to Rockford Fosgate, maybe it’s the radio itself. Battery switches are not expensive, but hate to see you start with the parts cannon.

[jhnmdahl]

Rockford Fosgate often publishes firmware updates to their head units on their website - maybe give that a shot? If you can't independently measure voltage, it's a bit of a crap shoot.

[Jab555]

Had this exact problem with cobalt r5. The dealer replaced ever single thing: head unit, harnes that plugs in from head unit to receiver, receiver. I learned that they typically replace the Rockford Fosgate Receiver PMX-8BB with refurbished ones that typically don’t resolve the issue either. After buying a brand new Reciever PMX-8BB https://rockfordfosgate.com/products/details/pmx-8bb/ the issue is 100% gone.

I have to say, this was an extremely annoying issue since we always listen to music with others on the boat.

One note, I do not recall seeing a low voltage message on the head unit. But other that that, it was identical to what your are experiencing.