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Canada - Engine, A/T Controls - ECM/TCM Adaptation

GROUP
ENGINE ELECTRICAL

NO.
01-36-004

DATE
JUNE 22/01

MODEL
XG300

SUBJECT

XG300 ECM/TCM (PCM) ADAPTATION TO PREVENT ENGINE SURGING DURING VARYING A/C LOADS

This bulletin provides the procedure to "teach" the XG300's ECM/TCM (PCM) to adapt to varying loads that the A/C system may demand on the engine.

This procedure should be used whenever:

1. The PCM has experienced an interruption of power (i.e.. battery disconnected).

2. The PCM has been reprogrammed.

3. The PCM has had its "adaptive values" cleared using the Hi-Scan Pro.

If this procedure is not performed the vehicle may exhibit an engine surge when the A/C compressor engages and disengages.

PROCEDURE

1. The engine temperature MUST be at least 75° C (167° F) before the PCM's learning function becomes active. Normal operating temperature is recommended.

2. With the transaxle in the Park position turn on the A/C. The engine speed will increase (approximately 1000 ~ 1500 rpm) then decrease back to normal.

3. Allow the engine to idle with the A/C on for approximately 10 minutes.

4. Turn off the engine. Wait 10 seconds for the PCM relay to de-energize. Restart the engine and confirm that the engine does not surge when the A/C is turned on. If it still surges, repeat steps 1 ~ 3.

5. Finally, test drive the vehicle with the A/C on. The engine should not surge when the A/C compressor engages. If it does, repeat steps 1 ~ 3.