Some advise please -
I'm replacing the CS-130 alternator in my 1990 Coupe with a CS-144 unit (using a unit list for a 1996 Olds Aurora Northstar Engine).
Everything I've read indicates that the two style alternators are plug and play - no conversion rewiring is required.
Everything seems to fit mechanically w/o any problems. Even has the same pulley. As expected, I needed to mill the upper flange fitting - removing 4mm so that it is narrow enough to fit into the existing bracket.
However, I'm still confused / concerned about the need to add a 35 ohm 1/2 watt resistor to the existing wiring harness or not...
Is the CS144 truly plug and play when replacing a CS130 - or do I need to add a resistor?
I measured the resistance from the disconnected positive battery cable (with the ignition on) to the "L" treminal on the disconnected alternator wiring harness - and measured 14 ohms. So there is some resistance, but less than half of the "recommended" (min) 35 ohms and nowhere close to the (max) of 350 ohms.
I'm not sure if the "battery icon" on the DIC is technically considered an idiot light - but I keep getting hung up on the fact that if I already had a CS130 installed in the vehicle, the CS144 should not require any additional wiring...
What have others that made the change experienced? Did you add a resistor?
From various web pages:
"L-Terminal: This terminal is connected to the “Low” side of the warning lamp, with the lamp’s “High” side being fed by the ignition circuit. Some regulators require a 35-ohm resistance inline with this circuit if no lamp is used otherwise alternator damage may ensue. Some applications have a resistor connected in parallel to the lamp in case the lamp bulb opens up and burns out. The resistor will be there to provide a path for current and voltage. Some vehicles supply a 5Vdc reference to this terminal from their ECU or Computer; other vehicles don’t, so be aware of the various models of regulators. Other regulators may be tested by application of a 50-Ohm pull-up resistor to connect the L-Terminal to the 12Vdc source, I believe that any resistance between 35 Ohms (5-Watt resistor) and 500 Ohms (1/2 Watt resistor) can be used safely."
"The resistors provide a "tickle" for the charging sensor. The alternator was designed for a car that has a "dummy" light, which provides resistance for that sensor. So, if your car has no dummy light, there is no resistance, so there has to be a resistor somewhere in the system to provide a load."
The switched 'light' (terminal 1 on SI or 'L' on CS), must have 12V switched power with between 35 and 350 ohm resistance (typically the light itself). If below 35 ohm, the CS units will fail.
So if the above is true - I don't know what the resistance requirements are for the CS-144 designed for an Olds Aurora - Maybe I should add a resistor to the circuit just to be sure that I'm over 50 ohms...