Yellow sensor wire alternater problem

[crispy]

I have a just fitted a charge splitter to my Volvo 2002 which didn’t work until I connected the Yellow alternator sensor wire to the house battery pos. However although I have charging to both batteries I no longer have any alarm sound when key is turned to on. If I reconnect the sensor wire back to alternator I have alarm sound but no charge. I think it may have something to do with a diode in the instrument panel. Any suggestions?

 

[pvb]

If it charges OK, are you that bothered by the lack of an alarm sound? Volvo Penta panels are notoriously random anyway.

 

[halcyon]

I have a just fitted a charge splitter to my Volvo 2002 which didn’t work until I connected the Yellow alternator sensor wire to the house battery pos. However although I have charging to both batteries I no longer have any alarm sound when key is turned to on. If I reconnect the sensor wire back to alternator I have alarm sound but no charge. I think it may have something to do with a diode in the instrument panel. Any suggestions?

The yellow wire is the field supply, not a voltage sense wire, sounds like the problem.

Brian

 

[VicS]

The yellow wire is the field supply, not a voltage sense wire, sounds like the problem.

Brian

The wiring diagrams show that as brown wire I am wondering if there is a some form of "advanced "alternator regulator fitted eg a Sterling. They have a yellow sense wire.

I think we need more detail of what is fitted and exactly how the diode splitter has been connected and what if anything has been done to boost the alternator to compensate for the volts drop in the diode splitter. Also is it just a plain simple diode splitter or something more fancy.

Been head scratching on this for half the evening

 

[crisjones]

I have a just fitted a charge splitter to my Volvo 2002 which didn’t work until I connected the Yellow alternator sensor wire to the house battery pos. However although I have charging to both batteries I no longer have any alarm sound when key is turned to on. If I reconnect the sensor wire back to alternator I have alarm sound but no charge. I think it may have something to do with a diode in the instrument panel. Any suggestions?

The yellow wire on Volvo alternators is a voltage sense wire to ensure the alternator output compensates for any losses between alternator and battery bank. It should be connected to the house bank positive terminal for it to be most effective, however connecting as the OP has done is likely to be ok for most installations.
No idea why the instrument panel does not give an alarm when connected this way since the yellow wire should not really have any effect on the instrument panel.

 

[crispy]

Thanks for your thoughts. The alternator is probably the same as original as it has Keypart label on it. I will ask them the wire designation on Monday. The charge splitter is from ASAP 741002 and seems to be connected as instructions.