Cooling bravo 1 outdrive
 

Your going to need to get more info from your engine and here is what you need:TechMate Pro marine diagnostic tool, marine code reader .
Also check drive lube level in reservoir.

For easy alarms its allways good to have any smartcraft gauge like eco monitor or so.It show direct what alarm is it.
Without you can only scan the pcm with rinda software,techmate pro or merc software.
Michael

Thanks.for the input
 

That alarm could be caused by a dozen things. The outdrive isn't one of them. The only sensor for the outdrive is low gear lube.
Buy a Rinda Techmate scanner or take it to a pro to have it scanned.

Snoozer - I totally agree with getting the scan - I don't have one but it sure makes sense. We have a 226 Cobalt 7.4 mpi and I was getting an alarm that was driving me crazy - I check fluids, connections etc-- as stupid as this sounds it was an alarm for water depth. Somehow I activated the low depth feature to something like 15 ft of water - Talk about feeling dumb !!!!

all the very best

3pointstar

^^^^ This.

Examples

2004 33 Outlaw 496HO's. Had beep every min, anything off idle was solid beep. Scanned showed IAC code. Replace it and was good to go.

2005 382 fastech 525's. Sold beep anything over 3000 rpms or so. Scanned and end cause was bad water pressure sensor.

Yes, check easy stuff first before spending dollars on a scanner.

He needs to describe what alarm - there is 4 of them as for sounds. One alarm sound is dedicated for the gear lube bottle low gear oil only. That one alarm does not mean anything else but Low gear lube. Since his alarm goes away at idle it most likely not the dedicated gear lube low alarm so you are correct.

Added info on top of

ANd when scanning that fault code will show but not under low gear lube fault, it shows under another fault explanation - Anyone know what that would be ??

Other causes for this exact alarm --- The switch can go bad or The float can go bad in these as well. Also the float can get stuck to the bottom sounding off gear lube low oil alarm when in fact the gear oil is at the correct level. When one does not clean out the thick oil gel at the bottom of the reservoir - the float can stick sounding the alarm.

there is 236 fault codes and not counting any for DTS codes. And for the apps that have DTS there is NO IAC nor an alarm nor a IAC code for it. No IAC muffler for DTS either. Easily a third of all merc 496s have DTS. The OP has a lot of info missing including year model and engine serial number.

So for the Merc 496 owners how many different alarms is there that one can have at any given moment to go off ? How many things can make a alarm go off on a Merc 496 ? If you are unsure take a guess

first lets ask --- 496 mag what ? Mercruiser ? Volvo Penta ? Indmar ?

IMPORTANT can you reach full WOT because many faults will and or can put the engine into guardian mode. This alone helps pin point the possible issues at hand without even scanning the engine.

year model ?

engine serial number ?

OEM Stock app ?

Mechanical throttle and shift or DTS ?

Alarm what does the alarm sound like ? there is 4 of them as all 4 mean different things ?

What have you done to rule out the issue at hand ?

The alarm is like a check engine lite on an auto - They all need to be scanned - since you have an alarm(s) that means you have an actual fault and that can also be more than one issue at hand.

:flag: on the play there Bup...:) What Merc ECM application are you testing us on? MEFI 1,2,3, etc., 555 or one of the later models like the PCM-09 ECM module ?

Further thoughts - to answer your question - I will put out another question - when scanning Merc engines that use Mefi 1 - 2 - 3, if the gear lube was low and sounding an alarm would it show on the scan as a fault ?? and if so what would that show under and the scan fault wording ?

Since I already said it would show for PCM 555 - so what fault would that show under ?

And does this same fault show for ECM 555 ? if it does show, what would those fault listing words show and be under on a scan ? Keep in mind ECM 555 has alpha outdrives and Bravo outdrives for apps so how does that change things ?

You forgot PCM 012 after PCM 09 in the mix --- haha