Charging - CS Series Generator Terminal Identification
89Oldsmobile10SUBJECT: GENERAL INFORMATION ON CS SERIES GENERATOR WIRING
MODELS/YEARS: 1987-89 ALL MODELS
NUMBER: 89-T-115
CORP. REF. NO: 938133
DATE: August 1989
SECTION: 8A
The new CS series generators (CS121, 130 and 144) have slightly different requirements for turning on the generator than the older S1 models. The terminals in the four-way connector are used as follows:
"S" Terminal
This is the "sense" terminal. It is connected directly to a battery positive lead. It provides the generator with a battery reference voltage, so that the regulator can determine the level of charging needed. Some vehicles do not have this lead connected, because the generator also has an internal sense function which will operate if the lead is cut or broken.
"F/I" Terminal
This terminal is used for one of two purposes, depending on the model. First, on most models, the F/I terminal is the "field" terminal. It is used to turn on the generator thru an internal resistor. It is used on cars with gage clusters, and is connected directly to an ignition feed (no external resistance is needed). Secondly, this terminal may be used in service diagnostics.
"L" Terminal
This is the "lamp" terminal. It is used to operate the I.P. telltale warning lamp, and can also be used to turn on the generator. It is connected to the generator thru the resistance of the lamp or a resistor.
IMPORTANT: If this terminal is connected directly to either an ignition feed or a battery feed, without going thru a resistor or a bulb, the regulator will eventually be destroyed.
Note 1: Some vehicles may have wires to both the "F/I" and "L" terminals. Either terminal will turn
on the generator. In addition, some vehicles may have wires to both terminals, but only one will be connected on the other side of the bulkhead connector. This is done to commonize engine harnesses. Again, either wire will turn on the generator, and no power to one of the wires should not be considered a problem with the vehicle.
"P" Terminal
This terminal is not currently used on any application. It can be used to supply an engine speed output signal for a tachometer on diesel engines.