GMC G2500 Back Up Light Switch Guide for 1979-1989 Models
If your reverse lights are failing, the back up light switch is the likely problem—here’s how to choose the right replacement.
- The most critical step is to order the correct switch for your van's transmission type (automatic vs. manual).
- Symptoms are usually no reverse lights, flickering lights, or lights that stay on.
- Before replacing the switch, check the bulbs and the 'TURN B/U' fuse.
- Standard Ignition is a trusted aftermarket brand for this repair, offering a reliable and affordable part.
Is Your Back Up Light Switch Failing?
A faulty back up light switch is more than an inconvenience; it's a safety hazard and can get you a ticket. The symptoms are usually straightforward. If you notice your reverse lights won't turn on, flicker, or stay on even when you're not in reverse, the switch is the most common culprit. Sometimes, a worn shifter linkage can also cause intermittent issues, where you might have to jiggle the shifter to get the lights to work. Before replacing the switch, always check the simple things first: make sure the bulbs aren't burned out and check the fuse labeled "TURN B/U" in your fuse panel.
Choosing the Right Aftermarket Switch
For a vehicle like the '79-'89 G2500, finding original GM parts can be tough. Aftermarket parts are the most practical and affordable solution. Brands like Standard Ignition (also known as Standard Motor Products or SMP) are a reliable choice. They have a long-standing reputation for producing quality replacement parts that meet or exceed original specifications. Reviews often show that these parts fit correctly and solve the problem without issue.
Pro Tip: Avoid Common Ordering Mistakes
The single most important factor when ordering is your van's transmission type. The switch for an automatic transmission is completely different from the one for a manual transmission. There are also variations based on the specific year of your van. Always verify the part fits your exact year and transmission before ordering.
- Automatic Transmission: The switch is usually on the steering column inside the cab.
- Manual Transmission: The switch is typically a plunger-style unit on the transmission housing itself.
Known Issues, Recalls, or Service Bulletins
Searches for official safety recalls or Technical Service Bulletins (TSBs) from GM or the NHTSA specifically for the back up light switch on the 1979-1989 GMC G2500 did not find any relevant results. Any issues with this part are typically due to normal wear and tear over decades of use.
Replacement Cost
Replacing the back up light switch is an affordable repair. The cost of the part itself is low, and if you have some basic tools, it's a job you can do yourself. If you take it to a shop, labor costs will be minimal, usually less than an hour of work.
| Item | Estimated Cost |
|---|---|
| New Aftermarket Part (Standard Ignition) | $26 - $54 |
| Shop Labor | $75 - $150 |
| Total Estimated Cost (Shop Repair) | $101 - $204 |
Frequently Asked Questions
Where is the back up light switch located on my G2500?
For automatic transmission models, look under the dashboard at the base of the steering column. For manual transmission models, you will need to get under the van; the switch is located on the side of the transmission.
My reverse lights still don't work after replacing the switch. What now?
First, if you have an automatic, the new switch may need to be adjusted. It can slide slightly on the steering column to ensure it engages correctly when you shift into reverse. If that doesn't work, check for bad grounds at the tail lights or damaged wiring between the switch and the lights. A simple test light can help you trace the circuit to find where the power stops.
Is Standard Ignition a good brand for this part?
Yes. Standard Motor Products (SMP) is a well-regarded aftermarket manufacturer that produces parts under the Standard Ignition brand. They are known for making reliable, OEM-quality replacement parts that are a good value for repairs on older vehicles.
Can I still drive my van with a bad back up light switch?
Yes, you can still drive the van as the switch failure does not affect the engine or transmission's operation. However, it is a safety issue, as other drivers won't know you are reversing, and it may be illegal in your state. It's best to get it fixed promptly.
Technical Specifications
Varies by transmission. Automatic transmission models use a switch mounted on the steering column, often integrated with the neutral safety switch. Manual transmission models use a plunger-style switch on the transmission case.
We Have This Part in Stock
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.