Connector pinouts
Connector pinouts is an overview of electrical connector pinout information for the Pontiac Fiero.
This page is intended to organize connector locations, terminal functions, wire colors, circuit descriptions, model-year differences, and related wiring information.
Overview
Connector pinouts are useful for diagnosing electrical problems, repairing wiring, performing engine swaps, checking sensor circuits, testing the ECM, and understanding factory wiring.
Pinout information should be verified carefully because connectors, wire colors, and circuit functions may differ by model year, engine, transmission, and option package.
Major connectors
Common Fiero connector topics include:
- ALDL connector
- ECM connectors
- C203 connector
- C500 connector
- Instrument cluster connector
- Headlight connector
- Tail light connector
- Fuel pump connector
- Radiator fan connector
- Ignition module connector
ALDL connector
The ALDL connector is used for diagnostic access to the ECM.
Related topics:
ECM connectors
The ECM connectors contain engine-control wiring for sensors, injectors, ignition control, fuel pump control, ALDL communication, power, and grounds.
Related topics:
C203 and C500 connectors
The C203 and C500 connectors are important body and engine harness connectors. They are often discussed in engine swaps, wiring repairs, and drivetrain conversions.
Related topics:
Lighting connectors
Lighting connector pinouts are useful for diagnosing headlights, tail lights, turn signals, brake lights, marker lights, and interior lighting.
Related topics:
- Headlights
- Gen 1 headlight system
- Gen 2 headlight system
- Tail lights
- Turn signals
- Brake lights
- Headlight wiring
Instrument and interior connectors
Interior connector pinouts may be needed when diagnosing gauges, switches, lighting, audio wiring, HVAC controls, or interior accessories.
Related topics:
- Instrument cluster
- Temperature gauge
- Fuel gauge
- Factory radio
- Performance Sound
- Power windows
- Power locks
- Interior
Engine-swap use
Connector pinouts are especially important for engine swaps. Swap wiring often requires connecting donor-engine wiring to Fiero body wiring, power circuits, grounds, fuel pump control, gauges, charging, starter wiring, cooling fan control, and diagnostic wiring.
Related topics:
Notes
Connector pinout articles should clearly identify:
- Connector name
- Connector location
- Model year
- Engine
- Transmission, if relevant
- Pin or terminal number
- Wire color
- Circuit function
- Source of the information
Do not assume that a pinout from one model year applies to all Fieros.