For car enthusiasts and owners of classic vehicles from the 1980s, understanding your car’s health can sometimes feel like going back in time. Unlike modern cars equipped with OBD-II ports for easy computer scanning, vehicles from the 80s often require a more hands-on approach to diagnostics. If your check engine light is on in your vintage ride, don’t worry – you can still get to the bottom of it. This guide will walk you through how to scan cars from the 1980s using the check engine light’s blink codes, a method that taps directly into your car’s onboard computer without needing any fancy, modern scanning tools.
Decoding the Blink Codes: Long and Short Flashes
The onboard computer in many 1980s cars is designed to communicate error codes through the check engine light itself. It does this using a simple system of long and short flashes. Think of it as Morse code for your engine! A long blink represents the number “10”, and a short blink represents the number “1”. By counting these blinks, you can decipher the error code your car is trying to tell you.
Step-by-Step Guide to Reading Blink Codes
To initiate the scanning process and read these blink codes, follow these steps:
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Locate the Diagnostic Connector: For most 1980s vehicles, you’ll need to find the diagnostic connector. This is often located under the dashboard on the driver’s side. It might be a two-pin connector that is not immediately obvious like the OBD-II port in newer cars. Consult your car’s repair manual if you’re unsure of its exact location.
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Prepare a Jumper Wire: You’ll need a simple piece of wire to jump or connect the diagnostic connector terminals. A standard paper clip can also work if it’s sturdy enough.
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Connect the Terminals: With the ignition off, use your jumper wire to connect the two terminals in the diagnostic connector. This action essentially tells the car’s computer to start outputting the diagnostic codes.
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Turn the Ignition to “Run”: Insert your key into the ignition and turn it to the “run” position. This is usually two clicks forward for many car models. Do not start the engine.
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Observe the Check Engine Light: Now, watch your check engine light closely. It should begin to blink in a pattern of long and short flashes. Pay close attention to the sequence.
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Count the Blinks and Decode: Carefully count the long and short blinks. For example, if you see one long blink followed by two short blinks, this translates to a code of 12 (10 + 1 + 1). Repeat this process as the codes may cycle through more than once. Write down each code you observe.
Example: Interpreting Code 12
Let’s say, like in the original example, your check engine light blinks once long, then twice short. This sequence indicates code 12. For many Honda vehicles of that era, code 12 points to a problem within the Exhaust Gas Recirculation (EGR) system. The EGR system is crucial for reducing emissions by recirculating a portion of the engine’s exhaust gas back into the cylinders to lower combustion temperatures. A malfunctioning EGR valve or system is a common issue in older, high-mileage cars and while it needs attention, it’s often not an immediately critical problem.
Alt: Check engine light illuminated on the dashboard of a vintage car, indicating a potential engine issue requiring diagnostic scanning.
Finding the Error Code List for Your Car
Once you have the blink codes, the next crucial step is to find the specific error code list for your make and model of car. A generic code list might not be entirely accurate, as codes can vary between manufacturers and even specific models within the same brand.
The best way to find the correct list is to perform an online search. Use search terms like “[Car Make] [Car Model] 1980s check engine light codes” or “[Car Make] OBD-I error codes”. You can also consult a repair manual specific to your vehicle, which often includes detailed diagnostic information and code lists.
Below is an example of Honda Check Engine Light Error Codes from that era, which can give you an idea of what these codes represent:
Honda Check Engine Light Error Codes (Example)
- 0: ECU
- 1: Oxygen Sensor
- 3: MAP Sensor
- 5: MAP Sensor
- 6: Crank Angle Sensor
- 7: Throttle Angle Sensor
- 8: TDC Position Sensor
- 9: No. 1 Cylinder Position Sensor
- 10: Intake Air Temperature Sensor
- 12: Exhaust Gas Recirculation (EGR) System
- 13: Atmospheric Pressure Sensor
- 14: Electronic Air Control System
- 15: Ignition Output Signal
- 16: Fuel Injector
- 17: Vehicle Speed Sensor
- 20: Electronic Load Detector
- 22: VTEC System Malfunction
- 23: Knock Sensor
- 41: O2 Sensor
- 43: Fuel Supply System
- 45: System Too Rich or Too Lean
- 48: Primary Heated O2 Sensor
- 54: Crankshaft Speed Fluctuation Sensor
- 61: Primary O2 Sensor Circuit
- 63: Secondary O2 Sensor Circuit
- 67: Catalyst System
- 70: Automatic Transaxle
- 71-74: Random Misfire
- 80: Exhaust Gas Recirculation
- 86: Engine Coolant Temperature Circuit
- 90: Evaporative Emission Control System Leak Detected
- 91: Fuel Tank Pressure Circuit
- 92: Evaporative Emission Control System Insufficient Purge Flow
Alt: Interior view of a classic 1980s car dashboard, highlighting the analog gauges and vintage design elements.
Conclusion: Basic Diagnostics for Classic Cars
Scanning cars from the 1980s might not involve plugging in a modern scanner, but the blink code method provides a valuable way to understand what your car’s computer is trying to tell you. By carefully reading and interpreting these codes, and then consulting the correct error code list, you can gain important insights into potential issues and make informed decisions about maintenance and repair for your cherished vintage vehicle. Remember, this method provides a starting point for diagnosis, and for complex issues, consulting a qualified mechanic experienced with older cars is always recommended.
