Porsche Used Parts: Headlamp Switch for 911 SC 1980 – A Complete Guide

Finding a replacement headlamp switch for your 1980 Porsche 911 SC can be a challenge. New old stock (NOS) parts are scarce, and OEM replacements from Porsche can be expensive. That's where used parts come in. A used headlamp switch, if sourced carefully, offers an affordable and reliable solution. This guide covers everything you need to know: identifying the correct part, inspecting a used switch, installing it, and where to find quality used components.

Understanding the 1980 Porsche 911 SC Headlamp Switch

The headlamp switch in a 1980 911 SC is a multi-function unit. It controls not only the headlights (low/high beam) but also the parking lights, dashboard illumination, and sometimes the fog lights (if equipped). It's mounted on the dashboard to the left of the steering wheel, typically with a pull-out knob. The switch is known for its distinctive feel and the satisfying click when turned.

Common Issues with the Headlamp Switch

Owners of the 1980 911 SC often report that the headlamp switch can become intermittent or fail entirely. Symptoms include:

• Headlights flickering or not turning on.
• Dashboard lights dimming or going out.
• Difficulty turning the knob (stiffness or looseness).
• Burnt or melted contacts inside the switch due to high current draw.

These issues are often caused by worn internal contacts, heat damage, or corrosion over four decades. A used switch can be a perfect replacement if it's in good condition.

Why Consider a Used Headlamp Switch?

Used parts offer several advantages:

• Cost savings: A used switch is typically much cheaper than a new OEM or aftermarket unit.
• OEM authenticity: Used switches are genuine Porsche parts, ensuring the correct fit and feel.
• Availability: While NOS is rare, used switches are relatively easy to find from salvage yards or online specialists.

However, a used switch may have hidden wear. That's why careful inspection is critical.

What to Look for When Buying a Used Headlamp Switch

Before purchasing a used headlamp switch, you need to verify its condition and compatibility.

Visual Inspection

Ask the seller for clear photos or inspect in person:

• Condition of the outer casing: Look for cracks, heat distortion, or melted plastic.
• Internal contacts: If possible, open the switch casing (or ask about internal condition). The contacts should be clean, not pitted or burned. Slight discoloration is normal, but heavy pitting indicates failure.
• Knob and shaft: The knob should be tight and not loose. The shaft should move smoothly without binding.
• Wiring pigtail: Some switches come with a wiring harness attached. Check for frayed wires, corrosion on terminals, or broken connectors.
• No signs of water damage: Rust or white corrosion indicates moisture ingress.

Part Numbers and Compatibility

The correct part number for a 1980 911 SC headlamp switch is 911.613.101.00 (or superseded numbers like 911.613.101.01). Some later 911 models use a similar switch, but the wiring and mounting may differ. Always verify:

• The switch is for a 1978-1983 911 SC (G-body).
• The connector type matches your car's harness. The 1980 model typically uses a rectangular plug with multiple pins.
• If your car has fog lights or a rear wiper, ensure the switch has the correct positions.

Check with the seller about the donor car's year and any modifications.

Testing Before Purchase

The best way to assess a used switch is to test it with a multimeter or a test light. If you're buying online, ask the seller to test continuity:

1. Rotate the knob through all positions (Off, Parking, Headlights).
2. Pull the knob for high beam (if applicable).
3. Check for smooth operation and consistent continuity on the relevant terminals.

If testing isn't possible, look for sellers who offer a return policy or warranty on used parts.

Installation Tips

Replacing the headlamp switch in a 1980 911 SC is a straightforward job that most DIYers can handle. Here are practical tips:

Safety Precautions

• Disconnect the battery negative terminal before working on any electrical components.
• Have a wiring diagram handy (the 1980 911 SC wiring diagram is available in the factory workshop manual).
• Use dielectric grease on connectors to prevent future corrosion.

Step-by-Step Summary

1. Remove the lower dashboard panel: unscrew the two screws under the dash and pull the panel carefully.
2. Locate the headlamp switch: it's behind the left side of the dashboard, clipped or bolted in.
3. Disconnect the wiring harness: press the release tab on the connector and pull it off the switch.
4. Remove the switch retaining nut: a large plastic or metal nut holds the switch to the dashboard. Turn it counterclockwise.
5. Replace with the used switch: insert the new switch, tighten the retaining nut, and reconnect the wiring harness.
6. Test operation: reconnect the battery and test all light functions before reinstalling the panel.

Note: Some 1980 911 SCs have a dash-dimmer rheostat integrated into the same assembly. Ensure the used switch includes that if your car has it.

Where to Find Used Parts

Since we're not mentioning marketplaces, focus on specialist sources:

• Porsche salvage yards: Many independent scrap yards specialize in vintage Porsches. They often have tested used parts and can provide the correct switch.
• Porsche clubs and forums: Member classifieds can be a great source; ask for part history and photos.
• Independent Porsche mechanics: They sometimes have leftover parts from customer upgrades.
• Online specialty retailers: Some shops focus on refurbished or used Porsche electrical components.

When contacting a supplier, be specific: “I need a working headlamp switch from a 1980 Porsche 911 SC, part number 911.613.101.00.” Ask about condition, testing, and return policies.

Final Recommendation

A used headlamp switch for your 1980 Porsche 911 SC can be an excellent economical choice—if you do your homework. Prioritize suppliers who can confirm the switch is tested and in good working order. If you find a visually clean switch from a known vintage Porsche specialist, it's likely a solid buy. For peace of mind, consider a refurbished switch that has been disassembled, cleaned, and had contacts rebuilt. That option blends the authenticity of a used part with restored reliability.

Remember: the headlamp switch is a safety-critical component. A faulty switch can cause lights to fail at night. Whether you choose a used, refurbished, or new aftermarket switch, ensure it meets OEM specifications. With careful sourcing, a used Porsche 911 SC headlamp switch will keep your classic car shining bright for many more miles.