Volvo D2-40B Alarm

[MurrayAtkinson]

Hi All, the alarm is sounding on my D2-40 when the battery switch is on, before pressing the power button, when the screen is still blank. The engine runs fine. I guess there's a loose connection somewhere, but I can't find one. Any ideas please?

[SofiaB]

Have you checked to see if your engine is subject to a recall? My D2-55F was having all kinds of strange issues until one day it didn't start. Researching online I found a recall notice and Volvo replaced the MDI unit under the recall. D2-40 was listed on the recall. I had various issues including alarm sounding when it should not be sounding. If your serial number is listed I suggest getting it fixed before leaving too far and also because of possible unsafe conditions such as the engine starting in forward gear, full throttle; ask me how I know. If it is the MDI unit, it's a 10 minute job. Volvo asked if I wanted to do it myself but my Volvo Dealer/Mechanic happened to be in the marina when it failed. Good luck!

[MurrayAtkinson]

Thank you SofiaB. I entered the serial number on the Volvo recall search page (https://www.volvopenta.com/marinelei...formation.html) and it just said there were no recalls for that serial number, but didn't confirm what item I was searching about, so I tried with a made up number and got the same result. Consequently I have low confidence in that system. Do you have a link to the page you looked under?

[GordMay]

Greetings and belated welcome aboard the CF, Murray.


Quality Campaign. Q0138, D1,D2. MDI, replacement
D1-13F, D1-20F, D1-30F, D2-40F, D2-50F, D2-55F, D2-60F, D2-75F
➥ https://www.hisse-et-oh.com/store/me...3668db563d.pdf

Before starting any work, check the engine serial number in Product Centerto determine if the engine is affected by this or any other campaign
➥ https://www.volvopenta.com/marinelei...formation.html

[DougR]

Does the alarm continue to sound after you turn the panel on? And if so, what alarm is indicated?

[tkeithlu]

Sounds like a closed connection rather than a loose wire. In some installations, oil pressure sensors sound as soon as you apply power, because you have no oil pressure while the engine is off. Oil pressure keeps the switch (sensor) open. But, this is specific to your installation, and didn't occur previously. So, turn on the power, adjust your hearing protection, put your multimeter on "DC volts," and trace backwards from the alarm to the source of power for the alarm. It's getting in there somehow, and it's not likely to be complicated.

[MurrayAtkinson]

Originally Posted by DougR

Does the alarm continue to sound after you turn the panel on? And if so, what alarm is indicated?

Yes, none.

[MurrayAtkinson]

Originally Posted by tkeithlu

Sounds like a closed connection rather than a loose wire. In some installations, oil pressure sensors sound as soon as you apply power, because you have no oil pressure while the engine is off. Oil pressure keeps the switch (sensor) open. But, this is specific to your installation, and didn't occur previously. So, turn on the power, adjust your hearing protection, put your multimeter on "DC volts," and trace backwards from the alarm to the source of power for the alarm. It's getting in there somehow, and it's not likely to be complicated.

I won an hours electrical diagnosis in the xmas draw! so the electrician did this and the source of the power to the alarm is the EVC or MDI or whatever name the black box is going under. There was no supply from any of the sensors. Opening the box didn't reveal anything, accessible terminals cleaned etc, but no change. Guess a component in there is misbehaving.

[MurrayAtkinson]

It appears this issue stems from the MDI/EVC control unit (see above) solutions are to replace the box like for like (£600ish) replace it with non-electronic part (possibly cheaper and more reliable but a lot of time to source all the components). Meanwhile, disconnecting the power to the noisy alarm reveals there is a second alarm sounder which emits the double tone on switching on, much more quietly. Will test whether this also sounds for an actual alarm. So temp solution is do nothing!