Volvo Penta 2003 low oil pressure alarm not working

[NealB]

Our boat has got the standard VP engine panel.

The oil warning, water temperature, and non charging lights all come on correctly when the power switch is pushed on, go out correctly when the engine runs, and come on again when the engine is stopped.

So all ok there, and, in particular, suggests that the oil pressure sender unit is working ok.

However, the low oil pressure alarm doesn't sound, either when the panel is switched on, or when I stop the engine.

So ..... oil light ok, oil alarm useless.

The alarm sounds loudly when the test button is pressed.

I've cleaned, tightened and Contralubed as many connections as I can find.

Can any of you clever electrical types suggest other obvious things to try please?

Thanks.

Ps just in case it's relevant, the rev counter doesn't work either but that's lower down the to do list.

 

[davidej]

Our boat has got the standard VP engine panel.

The oil warning, water temperature, and non charging lights all come on correctly when the power switch is pushed on, go out correctly when the engine runs, and come on again when the engine is stopped.

So all ok there, and, in particular, suggests that the oil pressure sender unit is working ok.

However, the low oil pressure alarm doesn't sound, either when the panel is switched on, or when I stop the engine.

So ..... oil light ok, oil alarm useless.

The alarm sounds loudly when the test button is pressed.

I've cleaned, tightened and Contralubed as many connections as I can find.

Can any of you clever electrical types suggest other obvious things to try please?

Thanks.

Ps just in case it's relevant, the rev counter doesn't work either but that's lower down the to do list.

No VP one ever does !

 

[NealB]

No VP one ever does !

Ahhhhh .... thank you!

 

[VicS]

Our boat has got the standard VP engine panel.

The oil warning, water temperature, and non charging lights all come on correctly when the power switch is pushed on, go out correctly when the engine runs, and come on again when the engine is stopped.

So all ok there, and, in particular, suggests that the oil pressure sender unit is working ok.

However, the low oil pressure alarm doesn't sound, either when the panel is switched on, or when I stop the engine.

So ..... oil light ok, oil alarm useless.

The alarm sounds loudly when the test button is pressed.

I've cleaned, tightened and Contralubed as many connections as I can find.

Can any of you clever electrical types suggest other obvious things to try please?

Thanks.

Ps just in case it's relevant, the rev counter doesn't work either but that's lower down the to do list.

If the light performs as it should, but the buzzer does not sound, suspect a fault in the VP electronic module. Open circuited diode perhaps.

Its the hour counters that usually fail. If there is no rpm indication check power is going to the tacho and connections all the way to the W terminal.

 

[[70521]]

No VP one ever does !

Mine does.

 

[NealB]

If the light performs as it should, but the buzzer does not sound, suspect a fault in the VP electronic module. Open circuited diode perhaps.

Its the hour counters that usually fail. If there is no rpm indication check power is going to the tacho and connections all the way to the W terminal.

Thanks Vic.

I can cope with checking connections on the rev counter, but performing surgery inside the bla k box is probably above my pay grade.

 

[Billjratt]

Don't know the volvo circuit so forgive perhaps silly questions and suggestion.
Is this audible alarm supposed to sound when ANY error light is on or only the oil pressure?
If so, as Vic suggests it is likely to be a diode failure. You can easily make a circuit up using one diode (from maplin, RS or your junkbox) per lamp.
One side of the buzzer will go to plus on the ign switch, the other* will go to the test switch and 'black box', Join the neg legs of all doides together and connect them to the * connection on the buzzer
Join each of the plus (banded)end of the diodes to the switch side the warning lamps. If the buzzer is solely for the oil circuit just connect it across the appropriate lamp.
If the revcounter problem is investigated you may be lucky in finding there is a common fix for both problems.

'

 

[VicS]

Don't know the volvo circuit so forgive perhaps silly questions and suggestion.
Is this audible alarm supposed to sound when ANY error light is on or only the oil pressure?
If so, as Vic suggests it is likely to be a diode failure. You can easily make a circuit up using one diode (from maplin, RS or your junkbox) per lamp.
One side of the buzzer will go to plus on the ign switch, the other* will go to the test switch and 'black box', Join the neg legs of all doides together and connect them to the * connection on the buzzer
Join each of the plus (banded)end of the diodes to the switch side the warning lamps. If the buzzer is solely for the oil circuit just connect it across the appropriate lamp.
If the revcounter problem is investigated you may be lucky in finding there is a common fix for both problems.

'

You will find the circuit in the owners manual
but here it is with the lowpressure warning light and the associated diode ringed in red

 

[Elemental]

My rev counter works after finding a broken lead (internal break - nothing visible) on the stbd side of the engine near the earthing point

My alarm sounds for temp overheat - nothing sounds when I switch on.

 

[VicS]

Thanks Vic.

I can cope with checking connections on the rev counter, but performing surgery inside the bla k box is probably above my pay grade.

My rev counter works after finding a broken lead (internal break - nothing visible) on the stbd side of the engine near the earthing point

My alarm sounds for temp overheat - nothing sounds when I switch on.

I belive the alarm buzzer will sound when tested or in the event of an overheat or low oil pressure while the engine is running. ITYWF that the complex nature of the electronic module is designed to prevent the alarm sounding when the engine is not running, even though the warning light may light.

You can test for the correct operation of the alarm by shorting the sensors out while the engine is running. Then you should get the corresponding warning light to illuminate and the audible alarm to sound.

On reflection, and having referred to the manual, I suspect there may be nothing wrong. The above will confirm or otherwise.