View Full Version : 2002 X-Star - Low Voltage Alarm Problems

05-02-2005, 12:26 PM
I could really use some information on my boat's low voltage battery alarm. The boat is a 2002 MC X-Star w/ the 330hp LTR motor. Some days it will go off as many as 5-10 times. I really doubt something is wrong with the boat and I hope this is some sort of malfunction. If there is something wrong, I want to fix it ASAP. Here is some information -

It always goes off when:

-the boat has been running for quite a while (at least 30 minutes to an hour)

-the boat is at idle speed.... we are in the middle of a set swinging around to the rider after a fall

-regardless of whether or not the stereo is on

To stop the alarm, I kill the motor and can instantly restart the boat... the alarm does not prohibit a restart for the 5 minute period that I've read about

This alarm started happening late last summer when the boat had a single battery. This winter dual optima's were installed with a 200 amp relay for isolation.... the alarm still loves to sound. It will sound whether the stereo is running or not.

I see in the owner's manual that there are "other alarms" that monitor conditions such as oil pressure, engine and tranny temps. My oil is changed per the manual's recommendations, it is in operating range on the dipstick, and my oil pressure is very consistent. The engine temp, once at 160, never moves. The tranny fluid was changed this spring and is in operating range on the dipstick.

Please help!! Thanks in advance.

03-23-2010, 12:52 AM
What you describe is exactly what we have been experiencing for the past couple summers. We are getting ready to start our season here in the Southeast with our 2002 XStar and I was curious if you ever figured out why your alarm was going off as much as it was? I know its been quite some time since your post, but I am hoping this will jog your memory (or anyone else's for that matter) so that we can get to the source of this annoying alarm. In our case, it seems to be related to when our oil gauge reading dips down to the first line when in idle speed. Any insight or leads in how to remedy this would be greatly appreciated!


06-01-2010, 10:00 AM
Same issue here as well - any solution?

06-01-2010, 10:12 AM
Have you verified voltage at the battery and alternator with a digital multimeter when you are getting the alarm?

That is step 1.

My '02 X9 reads a full volt lower on the in-dash gauge than actual, but no alarm here.
Some have reported that removing, cleaning & reinstalling the MDC plug returns the gauge reading to actual, and can sometimes fix other gauge problems for those with the early stepper motor gauges like we have.

06-01-2010, 10:17 AM
robc, you might need a new oil pressure sending unit. Cheap and easy repair. My boat was doing the same thing a couple summers ago. Oil pressure seemed to fall and alarm would go off. Changed the sender and haven't had a problem since.

06-01-2010, 04:45 PM
I haven't checked any volts yet. Happened for the first time yesterday while we were on our last run out on the water. I'll check the volts next time.

What is the MDC plug?

06-01-2010, 06:06 PM
On the newer boats with electronic stepper motor gauges, there is a computer above the drivers kickpanel that controls the gauges. There is a large plug that has the sensor inputs wired through it.

Edit- might be MMDC, can't remember.

06-02-2010, 08:39 AM
Thanks, mine has the stepper motor gauges, just wasn't sure what the MDC or MMDC was.