Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1989 Geo Spectrum 2D Hatchback, AutomaticFACTORY OEM SERVICE PROCEDURE
Trouble Code Id Chart
SPECTRUM TROUBLE CODE IDENTIFICATION CHART
| Code | System Affected | Probable Cause | ||
|---|---|---|---|---|
| 12 (1) | No Dist. Reference Pulse To ECM | Open Circuit | ||
| 13 | Oxygen Sensor | Open Circuit | ||
| 14 | Coolant Temperature | High Temp. Indicated | ||
| 15 | Coolant Temperature | Low Temperature Indicated | ||
| 21 | TPS & Idle Switch Circuit | Open Or Short To Voltage | ||
| 22 | Fuel Cut-Off Relay Circuit | Open Or Grounded | ||
| 23 | Mixture Control Solenoid Circuit | Open Or Grounded | ||
| 25 | AIR VSV Solenoid Circuit | Open Or Grounded | ||
| 42 | Fuel Cut-Off Relay Circuit | Voltage High | ||
| 44 | Oxygen Sensor Circuit | Lean Exhaust Indicated | ||
| 45 | Oxygen Sensor Circuit | Rich Exhaust Indicated | ||
| 51 | PROM Error | Faulty Or Incorrect PROM | ||
| 53 | AIR VSV Solenoid Circuit | Voltage High | ||
| 54 | Mixture Control Solenoid Circuit | Signal Voltage High | ||
| 55 | ECM Error | Water Leaking Onto ECM Or Corrosion | ||
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Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.