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1979-1990 Plymouth Colt Headlight Switch: A Practical Guide

Flickering headlights or a dark dashboard in your Colt could mean it's time for a new headlight switch.

3 minutes to read 1979-1990 Plymouth Colt
Difficulty
2/5
Est. Time
0.75 hrs
DIY Doable?
✅ Yes
Shop Labor
$60-$120
Used OEM Price
$20-$50
🚫 Do not drive — If your headlights are not working or are unreliable, it is not safe to drive the vehicle at night or in low-visibility conditions.
Key Takeaways
  • Headlight switch failure is common for cars of this age due to heat and wear on internal contacts.
  • Symptoms include flickering lights, total light failure, or a non-working dash light dimmer.
  • New aftermarket brands like Standard Ignition are a reliable replacement, as new OEM parts are no longer available.
  • Replacement is a simple DIY task for most owners, typically taking under an hour.
The headlight switch in your Plymouth Colt is the main control for all your exterior and interior lights. It's more than just an on/off button. This switch sends power to your headlights, taillights, and parking lights. It also contains a small variable resistor, called a rheostat, that allows you to dim or brighten your instrument panel lights by turning the knob. On cars of this era, all the power for the headlights runs directly through this switch, which can cause it to get warm and wear out over time.

Is Your Plymouth Colt's Headlight Switch Failing?

For a vehicle from the 1980s like the Plymouth Colt, electrical components will eventually wear out. The headlight switch is no exception. Because it handles high electrical loads, the internal contacts can corrode or degrade from heat and age. While there are no widespread, specific recalls or service bulletins for the Colt's headlight switch, the symptoms of failure are common to most cars from this period.

Top Symptoms of a Bad Headlight Switch

If you notice any of these issues, your headlight switch is the likely culprit:

  • Lights Don't Turn On: The most obvious and serious symptom is when your headlights or taillights fail to turn on at all.
  • Flickering Lights: Headlights that flicker or cut out while you're driving can be caused by worn contacts inside the switch. The internal circuit breaker may be tripping due to high resistance.
  • Dash Lights Malfunction: If you can't adjust the brightness of your dashboard lights, or if they don't work at all, the rheostat inside the switch has likely failed.
  • Mode Selection Issues: Trouble switching between low beams and high beams, or having the switch not 'click' into place properly, points to internal wear.

Safety First

Failing headlights are a critical safety issue. If your lights are unreliable or don't work at all, the vehicle is not safe to drive at night or in poor visibility conditions. Address the problem immediately.

Choosing the Right Aftermarket Switch

Finding a new original equipment (OEM) headlight switch from Mopar for a 1979-1990 Colt is nearly impossible today. Your practical options are a used OEM part from a salvage yard or a new aftermarket part.

  • Used OEM: This can be a cheap option, but you risk getting a part that is near the end of its own life.
  • New Aftermarket: This is often the best choice. Brands like Standard Ignition (Standard Motor Products) produce new switches that meet original specifications and are a reliable replacement. They are engineered to be a direct fit and provide a long-term solution.

Pro Tip: The 1979-1990 Plymouth Colt spans several vehicle generations. This means there are different headlight switches for different years. Always verify that the switch you are buying is listed as a direct fit for your specific model year before purchasing.

Headlight Switch Cost for 1979-1990 Plymouth Colt

Part Type Estimated Cost
New Aftermarket (e.g., Standard Ignition) $42.98 - $128.94
Shop Labor for Installation $60 - $120
New OEM (Mopar) Discontinued
Used OEM $20 - $50 (Varies by source)

Frequently Asked Questions

Can I replace the headlight switch myself?

Yes, this is a DIY-friendly job for most people with basic tools. The process generally involves disconnecting the battery, pressing a release button on the switch to remove the knob, unscrewing a retaining nut on the dash, and then unplugging the electrical connector from the old switch. It typically takes less than an hour.

Are there any recalls for the Plymouth Colt headlight switch?

No. Searches of the National Highway Traffic Safety Administration (NHTSA) database show no recalls or specific defect investigations for the headlight switch on the 1979-1990 Plymouth Colt.

My headlights work, but my dash lights don't. Is it the switch?

Almost certainly. The dimmer function for the instrument panel lights is integrated into the headlight switch assembly. When it fails, it usually doesn't affect the exterior lights. A new switch should solve the problem.

Why do my headlights flash on and off by themselves?

Headlight switches on older cars have an internal circuit breaker. When the switch gets old and corroded, electrical resistance increases, creating heat. This heat can cause the breaker to trip, cutting power to the lights. As it cools, it resets, and the lights come back on, creating a dangerous flashing or cycling effect. This is a strong sign that you need a new switch.

Technical Specifications

OEM Part Numbers: 3747216 3747218 3747821 3747862

Varies by model year. Most are 8 or 9-terminal switches, often with a built-in rheostat for dash light dimming. Knob and shaft are typically removed by depressing a spring-loaded button on the switch body.

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Article researched & written by
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Meet Wrenchy → Updated Apr 19, 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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