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1975-1981 Chevrolet G20 Back Up Light Switch Replacement Guide

Get your reverse lights working reliably on your classic Chevy G20 van.

3 minutes to read 1975-1981 Chevrolet G20
Difficulty
1/5
Est. Time
0.75 hrs
DIY Doable?
✅ Yes
Shop Labor
$60-$120
Used OEM Price
$10-$30
⚠️ Drivable, but... — Yes, but it is a safety risk as other drivers and pedestrians won't be warned that you are reversing.
Key Takeaways
  • The most common cause of reverse light failure, after bulbs and fuses, is a bad back up light switch.
  • For automatic G20s, the switch is on the steering column and may just need adjustment.
  • New aftermarket switches from a brand like Standard Ignition are a reliable and cost-effective repair.
  • This is a simple repair that most owners can perform themselves with basic tools in under an hour.
The back up light switch on your 1975-1981 Chevrolet G20 is a simple but important part. When you shift your van into reverse, this switch closes an electrical circuit. This action sends power to the white lights on the back of your van, letting other drivers know you are backing up and lighting the way in the dark. On G20s with an automatic transmission and a column shifter, this switch is usually part of the neutral safety switch, which is located at the base of the steering column inside the van. For the rare manual transmission models, the switch is typically screwed directly into the gearbox.

Is Your Back Up Light Switch Failing?

Before you blame the bulbs or fuses, check for these common switch failure symptoms. A bad back up light switch is a frequent cause for reverse light problems on these vans.

  • No Reverse Lights: The most obvious sign is when your reverse lights don't turn on at all when you shift into reverse.
  • Lights Won't Turn Off: If the switch fails in the 'on' position, your reverse lights might stay on constantly, no matter what gear you're in. This can confuse other drivers and will burn out your bulbs quickly.
  • Intermittent Lights: Sometimes the lights flicker or only work when you jiggle the gear shifter. This often points to worn internal contacts in the switch or a switch that has slipped out of adjustment.

Pro Tip: Check Adjustment Before Replacing

For vans with an automatic transmission, the switch is mounted to the steering column. These switches can sometimes be adjusted. Loosen the mounting screws slightly and rotate the switch until the reverse lights only come on when the shifter is in the 'R' position. This simple adjustment can sometimes fix the problem without needing a new part.

Choosing a New Aftermarket Switch

For a vehicle from this era, finding a new original equipment (OEM) part from GM is nearly impossible. The main options are a used part from a salvage yard or a new aftermarket part. For a simple switch, a new aftermarket part is the recommended choice for reliability.

Standard Ignition (Standard Motor Products): This is a widely available and reputable brand for this component. They are known for producing quality replacement parts that fit and function correctly. Reviews from mechanics and DIYers are generally positive, making Standard a dependable option for your G20.

Estimated Costs

Part Type Part Cost Shop Labor Cost Total Installed Cost
New Aftermarket (Standard) $26.08 - $53.37 $60 - $120 $86 - $173
Used OEM $10 - $30 $60 - $120 $70 - $150

Cost estimates are for reference only and may vary based on your location, the specific product, and your mechanic's labor rates.

Frequently Asked Questions (FAQ)

Where is the back up light switch on my 1975-1981 G20?

If you have an automatic transmission with a column shifter, look inside the van. The switch is mounted on the lower part of the steering column, near the firewall. If you have a manual transmission, the switch will be located on the side of the transmission itself, requiring you to get under the van.

Can I replace the back up light switch myself?

Yes, this is a very DIY-friendly job. For column-mounted switches, it only requires basic hand tools and can be done inside the cab. For transmission-mounted switches, you will need to safely raise and secure the vehicle on jack stands to gain access. The replacement involves unplugging the electrical connector and unscrewing the old switch.

Are there any recalls for the G20 back up light switch?

No. Searches of the National Highway Traffic Safety Administration (NHTSA) database did not show any recalls for the back up light switch on 1975-1981 Chevrolet G20 vans.

What happens if I don't replace a broken switch?

Driving without functional reverse lights is a safety hazard. Other drivers and pedestrians will not have a clear visual warning that your van is moving backward. While it may not prevent you from driving the vehicle, it can make you liable in an accident and may result in a traffic ticket depending on local laws.

Technical Specifications

OEM Part Numbers: 15679680

Typically a 2-terminal switch. Location is dependent on transmission type (column for automatic, transmission case for manual).

Wrenchy
Article researched & written by
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Meet Wrenchy → Updated Jul 21, 2026

The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

Year Coverage
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