If you’re working on a classic car or hotrod, chances are that you’ll need to install a GM 4 wire alternator at some point. This type of alternator is easy to install and reliable, making it a popular choice among DIY enthusiasts. In this article, we’ll take a closer look at the GM 4 wire alternator wiring diagram and provide you with everything you need to know to make your installation a success.
What Is a GM 4 Wire Alternator?
A GM 4 wire alternator, also known as a CS130 alternator, is a type of alternator that is commonly found in GM vehicles. It’s a compact and lightweight alternator that is designed to produce a high output of power even at low engine speeds. The CS130 alternator is widely used in hotrods, muscle cars, and other custom vehicles because of its reliability and easy installation process.
How Does a GM 4 Wire Alternator Work?
A GM 4 wire alternator works by converting mechanical energy from your engine’s crankshaft into electrical energy. The alternator uses a stator, rotor, and diodes to generate a high output of power. The stator is a stationary part of the alternator that contains a series of wire coils. The rotor is a spinning part of the alternator that contains a series of magnets. As the rotor spins, it passes by the stator’s wire coils, which generates an electrical current. The diodes convert this current into a DC voltage that your battery can use.
The CS130 alternator is unique in that it uses four wires to connect to your vehicle’s electrical system. These wires are labeled S, L, P, and B, and each serves a specific purpose. Let’s take a closer look at what each wire does.
GM 4 Wire Alternator Wiring Diagram
The GM 4 wire alternator wiring diagram is relatively simple and straightforward. Here’s a breakdown of what each wire does:
| Wire Label | Purpose |
|---|---|
| S | The S wire is the excitation wire, which tells the alternator to start producing power. This wire is usually connected to the ignition switch’s “on” terminal or a switched 12-volt source. |
| L | The L wire is the warning lamp wire, which is used to turn on the alternator’s warning light when the engine is running. This wire is usually connected to the warning light in your vehicle’s dashboard. |
| P | The P wire is the stator wire, which provides a reference voltage to the alternator’s internal voltage regulator. This wire is usually connected to the voltage regulator or a switched 12-volt source. |
| B | The B wire is the battery wire, which connects directly to your vehicle’s battery. This wire provides the alternator with a constant source of power to produce electricity. |
Now that you know what each wire does, let’s take a look at how to wire a GM 4 wire alternator.
How to Wire a GM 4 Wire Alternator
Wiring a GM 4 wire alternator is a straightforward process that can be done in a few simple steps. Here’s what you need to do:
Step 1: Disconnect the negative battery cable from your vehicle’s battery to prevent any electrical shock or damage.
Step 2: Locate the four wires on your GM 4 wire alternator. These wires should be labeled S, L, P, and B.
Step 3: Connect the S wire to the ignition switch’s “on” terminal or a switched 12-volt source. This will tell the alternator to start producing power when the engine is running.
Step 4: Connect the L wire to the warning light in your vehicle’s dashboard. The warning light should turn on when the engine is running to indicate that the alternator is working properly.
Step 5: Connect the P wire to the voltage regulator or a switched 12-volt source. This wire provides a reference voltage to the alternator’s internal voltage regulator.
Step 6: Connect the B wire directly to your vehicle’s battery. This wire provides the alternator with a constant source of power to produce electricity.
FAQ
Do I need to upgrade my wiring to install a GM 4 wire alternator?
It’s a good idea to upgrade your wiring when installing a GM 4 wire alternator. The CS130 alternator is designed to produce a high output of power, which means that it requires a larger wire size than your vehicle’s factory alternator. Upgrading your wiring will ensure that the alternator can deliver power to your electrical system without any voltage drops or other issues.
Can I replace my vehicle’s factory alternator with a GM 4 wire alternator?
Yes, you can replace your vehicle’s factory alternator with a GM 4 wire alternator. The installation process is relatively simple, and the CS130 alternator is a reliable and efficient alternator that can provide plenty of power to your electrical system. However, you may need to upgrade your wiring to ensure that the alternator can operate at its full capacity.
How do I know if my GM 4 wire alternator is working properly?
You can test your GM 4 wire alternator to ensure that it’s working properly. You’ll need a voltmeter to perform the test. Start by connecting the positive lead of the voltmeter to the B+ terminal on the alternator and the negative lead to a good ground. With the engine running, the voltmeter should read between 13.5 and 14.5 volts. If it’s reading lower than this, there may be an issue with your alternator or electrical system.
Can I install a GM 4 wire alternator without a voltage regulator?
No, you cannot install a GM 4 wire alternator without a voltage regulator. The P wire on the alternator provides a reference voltage to the internal voltage regulator, which is responsible for regulating the alternator’s output voltage. Without a voltage regulator, the alternator would produce a voltage that’s too high, which could damage your electrical system.
Can I install a GM 4 wire alternator myself?
Yes, you can install a GM 4 wire alternator yourself if you have some basic knowledge of automotive electrical systems. The installation process is relatively simple, and there are many resources available online to guide you through the process. However, if you’re not comfortable working with electrical systems, it’s best to have a professional install your alternator for you.
In conclusion, the GM 4 wire alternator is a reliable and efficient alternator that can provide plenty of power to your electrical system. By following the wiring diagram and installation instructions provided in this article, you can install a GM 4 wire alternator in your vehicle and enjoy dependable power for years to come.
