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Information About CS Generators

AllData Editor Note

When GM came out with its CS Generator Tester, GM began configuring most of its charging system testing around the use of the testing tool.

Things to know if you don't have GM's generator tester:
1. The CS generator has no provisions to be externally "Full Fielded" as the generators of old could be.
2. The CS generator only needs two wires to make it work, one to the Battery terminal and one to turn it on.
3. If the CS generator has a wire going to the L terminal of the generator (frequently referred to as circuit 225 and found in the B position of the generator connector), this circuit turns on the generator and any other additional wires in the 4 wire connector usually just monitor voltage or supply a tach ref.
4. When Ignition is in the run position, the B connector position circuit supplies a "Resisted" voltage reference to the generator which simply turns it on and has no impact on charging rate.
5. This "Resistence Factor" makes this a No Load Circuit. Do NOT attempt to test this generator by supplying a jumper wire from the Batt to the L terminal. If things don't smoke, life expectancy of the generator will still be reduced.