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It is possible for the battery to cause the ECM to fail but before jumping to conclusion, we can perform some test to determine if it is the cause. The ECM and ECT ECU are 2 different components so it might be something else.
When the OD light flashes, an error has been detected by the ECT ECU and here are the diagnostic procedures.
ECT ECU Codes
1. Turn ignition on. DO NOT start engine. Depress OD switch on shift lever to ON position.
Codes can only be retrieved with OD switch on. If OD switch is off, OD OFF light will be on continuously and will not blink codes.
2. Install jumper wire between terminals TE1 and E1 of DLC1 or DLC2 connector. See Fig. 5 and Fig. 6.
3. Note number of flashes from OD OFF light on instrument panel. If normal system operation exists, OD OFF light will flash once every .25 second. See Fig. 7.
4.If system is operating correctly and no code exists, turn ignition off and remove jumper wire. Perform MANUAL SHIFTING TEST under TRANSMISSION SHIFT TESTING to determine if problem is a electrical or mechanical transmission problem. Check system by
the symptom. See appropriate symptom under SYMPTOM TROUBLE SHOOTING.
5. If code exists, OD OFF light will blink once every .5 second. Number of flashes equals first digit of code. After a pause of 1.5 seconds, second digit will be displayed. See Fig. 11.
6. If more than one code exists, next code will be displayed after pause of 2.5 seconds. See Fig. 11. Smallest number code will display first and system will progress to largest code. Codes will be repeated.
7. Once code is obtained, determine probable cause and symptom. See CODE IDENTIFICATION table. For diagnosis and repair of codes, see DIAGNOSTIC TESTING. Turn ignition off and remove jumper wire.
Once repairs have been performed, codes must be cleared from ECT ECU memory.
Friday, May 21st, 2010 AT 3:33 PM