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Home >> Jeep >> 1990 >> Wrangler L6-258 4.2L VIN T 2-bbl >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Service and Repair
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Engine Control Module: Service and Repair

REMOVAL

1. Disconnect the negative battery terminal before removing electronic components.
2. The Micro Computer Unit (MCU) is mounted underneath the instrument panel between the glove box and heater A/C housing.
3. Remove the MCU mounting screws and lower the MCU.
4. Disconnect the MCU wiring harness. Remove MCU.

INSTALLATION

1. Connect MCU wire harness to MCU.
2. Position MCU under instrument panel in correct location and install mounting screws.
3. Connect negative battery terminal and test operation.
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