If you own a 1990 Chevy car, then you might need to understand the ignition switch wiring system for maintenance and repairs. The ignition switch is responsible for triggering the starter motor, controlling the engine’s ignition system, and powering up the electrical accessories. In this article, we will discuss the wiring diagram of the 1990 Chevy ignition switch, as well as its components, functions, and troubleshooting tips. By the end of this guide, you will have a better understanding of how the ignition system works and how to fix common issues.
What is an Ignition Switch?
The ignition switch is an electrical component that is located on the steering column of a vehicle. It is responsible for controlling the flow of electricity from the battery to the starter motor and the rest of the car’s electrical system. When you insert the key into the ignition switch and turn it, the switch triggers the starter motor to crank the engine. At the same time, it sends power to the ignition coil, which creates a spark that ignites the fuel-air mixture in the engine’s cylinders. Additionally, the ignition switch provides power to the car’s electrical accessories, such as the headlights, radio, and air conditioning system.
The 1990 Chevy ignition switch consists of several components, including the ignition lock cylinder, the electrical switch, the starter solenoid, and the wiring harness. The ignition lock cylinder is the part of the switch that accepts the key and enables it to turn. The electrical switch is the main component that controls the flow of electricity. The starter solenoid is responsible for engaging the starter motor when the key is turned. And the wiring harness is the collection of wires that connect all these components together.
Wiring Diagram of 1990 Chevy Ignition Switch:
The wiring diagram of the 1990 Chevy ignition switch consists of several wires that are color-coded for easy identification. These wires include the purple wire, the yellow wire, the red wire, the orange wire, the pink wire, the brown wire, the black wire, and the white wire. Each wire has a specific function and connects to a certain component of the switch.
The purple wire is the starter wire and connects to the starter solenoid. The yellow wire is the ignition wire and connects to the ignition coil. The red wire is the battery wire and connects to the positive terminal of the battery. The orange wire is the accessory wire and connects to the fuse block. The pink wire is the power wire and connects to the fuse block. The brown wire is the dimmer wire and connects to the headlight switch. The black wire is the ground wire and connects to the chassis. And the white wire is the horn wire and connects to the horn relay.
Here is a detailed wiring diagram of the 1990 Chevy ignition switch:
| Wire Color | Function | Connected Component |
|---|---|---|
| Purple | Starter | Starter Solenoid |
| Yellow | Ignition | Ignition Coil |
| Red | Battery | Battery Positive Terminal |
| Orange | Accessory | Fuse Block |
| Pink | Power | Fuse Block |
| Brown | Dimmer | Headlight Switch |
| Black | Ground | Chassis |
| White | Horn | Horn Relay |
Common Issues with 1990 Chevy Ignition Switch:
Problem 1: Key Won’t Turn or Stuck in the Ignition
If the key won’t turn or is stuck in the ignition switch, then it could be due to several reasons. One common cause is a worn out or damaged ignition lock cylinder. To fix this, you need to replace the lock cylinder with a new one. Another reason could be a faulty electrical switch or a damaged wiring harness. In this case, you need to check the switch and harness for any damage or corrosion and replace them if necessary.
Problem 2: Engine Won’t Start
If the engine won’t start when you turn the key, then it could be due to several issues. One common cause is a dead or weak battery. In this case, you need to check the battery’s voltage and recharge or replace it if necessary. Another reason could be a faulty starter solenoid or a damaged starter motor. To fix this, you need to check the solenoid and motor for any damage or wear and replace them if necessary. Additionally, a faulty ignition coil or spark plug could prevent the engine from starting. Check these components and replace them if necessary.
Problem 3: Electrical Accessories Not Working
If the car’s electrical accessories, such as the headlights, radio, or air conditioning system, are not working, then it could be due to a faulty ignition switch. Check the switch’s wiring harness for any damage or corrosion and replace it if necessary. Additionally, check the fuse block for any blown fuses and replace them if necessary.
Frequently Asked Questions (FAQs):
Q1: How do you test an ignition switch?
A: To test an ignition switch, you need to use a multimeter to check the switch’s continuity and resistance. First, disconnect the switch’s wiring harness and turn the key to the on position. Then, use the multimeter to test each wire’s continuity and resistance. If any wire fails to show continuity or has high resistance, then it indicates a faulty switch.
Q2: Can a bad ignition switch drain the battery?
A: Yes, a bad ignition switch can drain the battery if it fails to cut off the power to the car’s electrical system. This can happen if the switch is stuck in the on position or if there is a short circuit in the wiring harness that keeps the switch’s electrical contacts closed.
Q3: Can you bypass an ignition switch?
A: Yes, you can bypass an ignition switch by connecting the starter wire directly to the battery positive terminal or by installing a push-button switch that triggers the starter solenoid. However, this is not recommended as it can lead to a security risk and damage the electrical system.
Q4: How much does it cost to replace an ignition switch?
A: The cost to replace an ignition switch depends on the make and model of the car and the labor charges of the mechanic. On average, it can cost between $150 to $300 for a professional replacement.
Q5: How long does it take to replace an ignition switch?
A: The time it takes to replace an ignition switch depends on the complexity of the car’s electrical system and the experience of the mechanic. On average, it can take between 1 to 2 hours to replace an ignition switch.
Conclusion:
The ignition switch is a crucial component of the 1990 Chevy car’s electrical system. Understanding its wiring diagram and common issues can help you maintain and repair your car’s ignition system. By following the troubleshooting tips mentioned in this article, you can diagnose and fix common ignition switch problems. However, if you are not confident in your mechanical skills, it is recommended to seek professional help to avoid any further damage or safety hazards.
