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ECM/PCM Idle Learn Procedure

ECM Idle Learn Procedure

The idle learn procedure must be done so the ECM can learn the engine idle characteristics.

Do the idle learn procedure whenever you do any of these actions;
- Disconnect the battery.
- Replace the ECM or disconnect its connector.
- Reset the ECM.

NOTE: Erasing DTCs with the Honda PGM Tester does not require you to do the idle learn procedure.

- Remove the No.6 ECU (ECM) (15A) fuse from the under-hood fuse/relay box.
- Remove the No.19 battery (80A) fuse from the under-hood fuse/relay box.
- Remove PGM-FI main relay 1.
- Remove any of the wires from the under-hood fuse/relay box.
- Disconnect any of the connectors from the under-hood fuse/relay box.
- Disconnect the connector between the engine compartment wire harness and ECM wire harness.
- Disconnect the G2 terminal from the transmission housing.
- Disconnect the G1 terminal from the body.
- Disconnect the G101 terminal from the cylinder head cover.

Procedure
1. Make sure all electrical items (A/C, audio, rear defogger, lights, etc.,) are off.
2. Start the engine, and hold it at 3,000 rpm with no load (in neutral) until the radiator fan comes on, or until the engine coolant temperature reaches 194 °F (90 °C).
3. Let the engine idle for about 5 minutes with the throttle fully closed.

NOTE: If the radiator fan comes on, do not include its running time in the 5 minutes.