BF225 slow beep alarm at idle and low speeds

Background: I have an 05 Honda BF225 on a 22ft Mako center console. Motor has just over 800 hours.

I was out on the boat yesterday and intermittently started getting a slow beep alarm. The first time it happened was at idle after the boat had been ran for about an hour. Turning it off and then back on resolved the issue for a bit. About an hour later it happened again, this time i was just in gear, running about 3kts. Turning it off and on again made it disappear. It happened a final time when i was at about 10kts. The boat seemed to run fine the entire time, didn't go into limp mode or anything like that. Thinking it may be an O2 sensor issue, what are your thoughts? Thanks in advance guys.

Assuming you have the 4-light console (oil, alternator, overheat, and MIL lights) then shunt the service connector and pull the fault codes as has been described many times on this forum. A Code 1 (single blink about every 2 or 3 seconds) indicates a failed HO2 sensor OR a misfiring spark plug. If you need a write up on the procedure, shoot me an e-mail at [email protected].

Thanks for the reply, I have a 2-light console.

In that case I think you will need to get to a Honda Marine dealer to pull codes using the HDS computer.

The beeps can be a couple different things. Water in fuel, over heating, check engine etc. Pull the codes, so you dont have to go at it blind.

From what i have seen on this site, a slow beep is not indicative of overheating. Correct me if i'm wrong, but overheating produces a steady alarm and throws the motor into limp mode. I don't have a scanner readily available to me, but i do have a spare O2 sensor. Was considering popping it in and running it tomorrow. If I'm still getting the alarm then I'll take her into the shop.

Slow Beep is normally associated with a problem in the programmed fuel injection system. But that could be any one of a bunch of things - from a failed HO2 sensor, misfiring spark plug, failing coil, low fuel pressure, etc. See below - columns are keyed to console lights.

Oil Overheat MIL Alternator
Pressure (Red) (Red) (Red)
Long Intermittent ON (1) OFF (2) ON OFF Abnormal PGM - FI
Long Intermittent ON OFF OFF ON Abnormal alternator
Long Intermittent ON (1) OFF (2) ON ON Abnormal PGM - FI & abnormal alternator
Long Intermittent ON (1) OFF (2) ON OFF Abnormal PGM-FI & water in separator filter
Long Intermittent ON OFF OFF ON Abnormal alternator & water in separator filter

Well, that didn't come out very well! Send me an e-mail at [email protected] and I'll send you the full list in Excel.

Lets try something else...

Sorry 'bout that. Send me an e-mail.