Double beep twice, at ignition and during start at Merc 5.0 EFI 2001

FJ96

Hi!

Since a few days I get an additional double beep during the start of my 2001 Mercruiser EFI with Alpha One.

When I turn on the ignition, the sounder gives a double beep. This is what the engine did from the beginning on. And this double beep instead of one single beep should be standard for the 5.0 EFI with Mefi4. So it was told to me.

Now, when I turn the key from ignition to start, it gives an other doubl beep. But this is only during the start. No beeps any more, while it's running and there's no lack of power.

The only thing is, that the engine starts not so smooth anymore, as it did before.

I have the rinda tool and it shows to faults.

Any idea? Thanks

Cheers
Frank

GMSLITHO

Maybe weak battery’s 

FJ96

Both fully loaded by shore charger.

But I wonder if it's a problem of low voltage caused by a bad connection of the ignition wire or the ground wire.

Just checked the pins at the engine harness plug and wided them a little.

FJ96

Just made some additional checks:
1. Main battery switch voltage at battery and voltage at startor are the same. Seems to be ok.
2. opened the dash to reach ignition key. turned on ignition and bridged ignition and yellow red starter wire to start engine up. The same. Double beep while igition turned on and while starting.
3. put a voltmeter on purpe ignition cable (and ground) and started.
The voltage dropped to approx 9.5 volts during the start.
4. put the voltmeter on red/black plus cable of ignition switch (and ground) and started.
Again the voltage dropped to approx 9.5 volts during start.
5. put the voltmeter direct on battery during start
Starter battery went down to approx 11.5 volts during start
So battery seems to be ok.

Any opinions?

Thanks
Frank

212rowboat

Its your IAC, sir.  This is a classic example of one failing.  

FJ96

ok, does it throw a double beep during the starter is cranking?

When engine is running, there's no warning anymore. Not this every two minute-beeping...

Willhound

The two beep code indicates IAC and we just had an example where this was the case. But I have to tell you that ever since I got my 2000 FV270 with 5.7 EFI it's done the same thing. Same set up as you, just bigger block. Two beeps at key on, starts fine and two beeps again and then all good. Boat starts and runs fine. No other beeps any other time. A scope shows no errors.
Boat runs fine so I've just learned to ignore it. Mught be a bad connection to whatever sensor gives IAC info, I don't know.

FJ96

Thanks Willhound!
What changed at mine is that idle seems not to be so smooth. So that sounds like IAC too. I've got the IAC from my old block on the boat, as well as a brand new one. I'll try them tomorrow. Since school is still closed because of the virus, I took my son for "boat schooling". So I'm at the boat for the whole week and can test directly.
Cheers
Frank

rasbury

Mine has always done that also...I figured it was low oil pressure sensor before it started...I just put an ice filter in it..it was gone...