525 EFI Alarm
 

I have 2005 twin 525EFI's. I am getting 3 alarm beeps about 1 minute apart. Has anybody experienced this? A sensor of some sort??

Yes it's a sensor, your going to have to scan it to see which one

3 beeps indicates a warning. First you need to isolate which engine is triggering the warning. Turn the key on one engine at a time and see if the beeps persist on that engine. If the beeps persist and don't stop by turning the key off and on again, then the system is detecting that there is a failure of some sort somewhere. 3 beeps is usually an indicator of a sensor failure (ie: water pressure or temperature, oil pressure or temperature). It's pretty easy to figure out if you can get someone to hook up a scan tool; otherwise you're going to be guessing which one.

The beeps are like the check engine light on the car some sensor is reporting out of its parameter range or ignition related. A scan is needed of your engine. The current software that can scan Merc racing apps is needed. Diacom or, Merc G3.

www.rinda.com
You ought to buy a scanner. Best money you will spend on that boat.

It's the Starboard motor. I took it to the dealer this morning and they hooked it up to the computer. A couple old codes (50-60 hrs ago) but nothing new. They called Mercury and they don't know what it is either.

Did they look at active faults or historic?
You have a great dealer if you whipped in for a quick check and they accommodated you like that; especially if they put it on the hose, and ran the motor with the computer attached.


Swap the IACs from one motor to the other motor. Common failure. See if the problem follows the swap.

mercury is not going to say I don't know - they would have thrown out something even if it was a total 100 % guess - I promise they always do.

You need to post info what the engine is doing running thru out the rpms - can you achieve max rpm's, does it idle smoothly or rough, easy start or hard, accelerates normally ? Stalls - will not restart easily and so on and so. You posted a dart board and the only answer you are going to get is the darts. More info is needed. Year model and engine serial would be good as well.

Dealer clears old codes (low drive oil reservoir, block water pressure low) and now the block water pressure low code came back. He disconnected that sensor but the 3 beeps still occur. His plan now is to start disconnecting each sensor one by one to try and isolate the problem one.

The engine is running fine. It starts good, idles normal, nothing out of the ordinary. I was out and it ran fine for 3-4 hour yesterday but it started to beep as I came to a no wake into the marina to load up. Originally I thought it might be a little low on drive oil so I didn't look at it until I got home. Fluids were all good. Even going slow into the marina, it didn't sound any different than normal.

here I believe there is at least 10 / 3 beeps faults for the HP 525 and YES sea water pressure failure is one of them - the 3 beeps for sure. You can have a bad sensor or shorted or a real water pressure / volume issue. Start with changing to a new sensor or least cleaning up ur old one. and make sure all connections are good to it.

Bryan for the 525 IAC is 5 beeps or least should be thru merc. FYI

Do you need me to list some of the 3 beep sensor faults ?

Well if the water pressure code came back , check what the sensor reads with out running and running to see what the sensor reads. Just replaced one that read 0 psi with 15 psi manually applied.

Dealer got a list of them. They thought for sure it would be the block pressure sensor since that code came up historically and again after they cleared the codes but they thought that by unplugging it, the beeping should have stopped?

Dealer went through and individually disconnected each sensor on that motor and alarm still sounds. In reading through Mercury's 525EFI manual, it looks like most of the 3 beep alarms have 15 second intervals? Mine is longer between alarms but not always the same. Sometimes it will be a minute between and others it may be 2 minutes. Just when you think problem solve, 3 beeps!! Maybe a computer glitch?

Switch PCMs between motors. That would eliminate or point toward wiring harness.

With the software it really should not be this much of an issue. Run the engine and monitor the sensor outputs. The sensor and or wiring to it will stand out. The information from the problem circuit would be skewed, too high too low or just fixed (computer puts a fixed value so it can continue to operate). Unplugging the sensors would activate a different code as the PCM would not see even the sensor rather than a sensor out of range.

You can also the software's data logging (log some new data) and go back and look for an intermittent issue.

I had the exact same thing happen to my 600sci last weekend and it was the water pressure sender on top of the oil cooler, it was plugged with hard water so Nordic replace it but I think it would still work by just cleaning it out they said it is very common. It is very easy to get at to check its on the left side on to of the oil cooler on the back of the engine, the new one was $129.

Remember 525 EFI is completely digital, not analog like a 502 MPI, it's a warning indicator when does it come on, those of us race 525 efi's know that the first indicator of 3 beeps is when you're at the rev limiter of 5400 RPM (stock trim), this will happen with a 24 pitch under normal condition and a 26 pitch prop with some trim. What is your running temperature, if you're running digital gauge, running temperature should stay under 160 degrees, if you sucked up some weeds while running check your filtration box and clean it if necessary, oil pressure will also sound off if it's a digital gauge, also watch for carbon build-up in your throttle yoke, this will cause a delay in dropping the engine back down to an idle from cruising speed, this will also cause an alarm. When are you located and I'll tell you were to take it??? I know all the codes on a 525 EFI, mine was built from a 502 to a 635 and produces almost 900 HP (N.A.) 1200 HP under 3.5 boost if I wanted it. The 860 HP with 920 FT:LB is enough for a 28 foot boat. They're are really under-powered for single engine application (just a 502 MPI on steroids).

Here all of the beep codes . . .
Seawater Pressure Sensor Failure, Coolant Temperature Sensor Failure, Oil Pressure Sensor Failure, Oil Temperature Sensor Failure, Charge Temperature Sensor Failure, Seawater Pressure Sensor Failure, Coolant Temperature Sensor Failure, Oil Pressure Sensor Failure, Oil Temperature Sensor Failure, Charge Temperature Sensor Failure, Fuel Pump Failure Fuel Pressure Sensor Failure, Cam Sensor Rationale, Throttle Position Sensor Failure, Low Battery Voltage, & Battery Range high or low.

525 Mercury Racing 5 Beeps Alarm
 

Hello All,

Wanted to see if anyone could help me with this issue.... I have a 525 Mercury Racing EFI which has been recently serviced but now has 5 beeps every 55 seconds. My mechanic scanned and this is what came back:
https://cimg4.ibsrv.net/gimg/www.off...36ce2cc43.jpeg
He said that the first item "IDLE MAP STR" is what is causing it and the others are just showing up because those sensors are not hooked up. He noted that it would be the IAC so i replaced with a brand new one. However it came back (alarm). Also I notice the idling is low and a little shaky so it has to all be related. Any one help point me in the right direction? It would be greatly appreciated.

Thank you!!!

Found in a 2013 thread that its being caused by the MAP. Not saying this is it but check the volts output of the MAP

https://www.offshoreonly.com/forums/...y-60-secs.html

Another thread, but never came back with results
https://www.offshoreonly.com/forums/...r-fault-2.html

Hi, I am having the same issue. What was your fix / solution? Thanks Kramer

You have to scan it find out. Other wise you are just throwing parts at a problem you have no idea what it is.
Best bet is to buy a Rinda scanner and have it on hand.

Your "beeps" are your Check Engine Light in an automobile. Same exact thing. As such, same exact diagnosis procedures.