My Volvo Penta 2001 has non-standard "after market" wiring and I am trying to work out why the charge light is staying on. Probably it needs a new alternator, but with poor access, I am hoping it is actually doing its job.
The evidence- keeping in mind the wiring is bodgy:
Battery is kept charged by a solar panel. Voltage around 12.7V. Oil, temperature and charge lights all come on prior to start as normal. Engine starts OK. Charge light stays on. Revving the engine does not make any difference. Measuring the battery voltage with engine running, it stays at the 12.7V. Alternator is rated 40A 14V.
I would expect to see 14V at the battery, but I am hoping someone will tell me that the regulator has decided that 12.7V on the battery is enough, and cut the alternator out. (Got to live in hope.)
Over to the electrical wizards....
Yarra you know the alternator is not charging, the good news is its more chance the regulator is pooped, other than the alternator complete. Take the unit a auto Sparkey to prove it. If the motor is running and the batt isn't 100% charged you you should see 14.5 v ish
I would agree the regulator is buggered. Pull off the alternator and remove the regulator. Use the part number and brand name in Google picture search. You maybe surprised by the number of motor vehicles that share the same part.
Give the alternator a tap with a hammer whilst the engine is running. Sometimes the knock will jar worn brushes and start the alt charging and the lamp will go out. This won't fix the problem but it can help diagnose what may be wrong.
It is also a good trick that can get you out of trouble. I drove a car for about 12 months that required a tap on the alternator every time you started the engine. I eventually got around to replacing the brushes,,, the missus was sick of it.
