voltage alarm

[smacks12]

i have a 2001 4.3 volvo penta and yesterday i was getting random alarms and the battery symbol would light up and i watched the voltage gauge drop to the lower end of the gauge which is ten volts, then suddenly it would stop doing it as if nothing had happened at all. being worried i took the alternator out and had it bench tested at a napa shop. they said it was fine. so i put the alternator back in, wirebrushed all terminals and connected. i re-checked the battery terminals, the starter terminals, and engine grounds. what else should i be looking for? any suggestions. i also changed the ignition switch about a month ago and all terminals seemed fine .

 

[bruceb58]

Re: voltage alarm

i have a 2001 4.3 volvo penta and yesterday i was getting random alarms and the battery symbol would light up and i watched the voltage gauge drop to the lower end of the gauge which is ten volts, then suddenly it would stop doing it as if nothing had happened at all. being worried i took the alternator out and had it bench tested at a napa shop. they said it was fine. so i put the alternator back in, wirebrushed all terminals and connected. i re-checked the battery terminals, the starter terminals, and engine grounds. what else should i be looking for? any suggestions. i also changed the ignition switch about a month ago and all terminals seemed fine .

Next time this happens, measure the voltage of the alternator output to see what you have. The output that goes to the idiot light may be bad but that wouldn't be tested by the Napa test. Unfortunately, you likely need that output since it is also the one that likely powers your fuel pump relay

 

[smacks12]

Re: voltage alarm

does anyone know where i can get a schematic with that type of detail? the schematic i have doesn't show any connections to the idiot light . thanks

 

[bruceb58]

Re: voltage alarm

Obviously its in the service manual but DonS has posted a generic one many times. It won't have the idiot light on it but it just wires to one of the terminals I mentioned...probably L2. One side of the idiot light will be wired to 12V and the other to L1. When L1 does not put out the proper 12V, the light will be on. L1 comes from the voltage regulator of the alternator.

 

[smacks12]

Re: voltage alarm

started investigating the wires under the dash, found a fuse holder on a purple wire under dash that when wiggled shut all the dash off, but didn't cut the engine off. i think i may have found the problem. one other note to mention is when the alarm goes off, it is very loud as if it is under the dash but i can't figure out where it is. this may sound dumb but is there any way it could be comming out of a speaker thats under the dash. thanks