colburge wrote:GR124 wrote:hi guys, so I get a better understanding of this thread and for the simple people like me what is "P&D alternator not L&S"
A P&D alternator has a 'P' Terminal and a 'D' terminal connector, as well as B+. The 'P' terminal is the phase output voltage to the vehicle PCM. The 'D' terminal is the driver input voltage from the PCM. The output voltage of the alternator to B+ is controlled by the PCM increasing or decreasing voltage to the 'D' terminal (field control unit) based on idle speed and air intake temperature.
L & S alternators look exactly the same including the plug but it has a full regulator inside. 'L' terminal goes to one side of the dash battery light and 'S' is the sense terminal straight from battery. The output to B+ is controlled by the internal regulator by reading battery voltage at 'S' and comparing it to the output voltage.
Col
Big Thanks Col, makes sense now. I need this education, mechanical stuff I'm fine with but electrical, I struggle. Cheers mate
