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.
1995 Geo Prizm Base, StandardFACTORY OEM SERVICE PROCEDURE
Engine Control Module (ECM)
NOTE:
ECM is also known as Powertrain Control Module (PCM). All references to ECM include PCM unless specified otherwise.
Power for ECM is supplied through the EFI F-HTR fuse, located in fuse/relay block. The ECM distributes power or controls ground of various sensors, switches and solenoids for engine control.
ECM LOCATION
| Application | Location |
|---|---|
| Prizm | In Front Of Center Console, Under Heater Blower Case |
NOTE:
Components are grouped into 2 categories. The first category is INPUT DEVICES, which are components that control or produce voltage signals monitored by the ECM. The second category is OUTPUT SIGNALS, which are components controlled by the ECM.
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.