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Home >> Chevrolet >> 2004 >> Optra Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 1.8L (L79) - DTC P1115 To DTC P1655 >> DTC P1397 >> Test Description
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Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. 1:  The diagnostic system check prompts the technician to complete some basic checks and store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data taken when the malfunction occurred. The information is then stored on the scan tool for later reference.
  2. 6:  The replacement ECM must be reprogrammed. Refer to the latest Techline procedure for ECM reprogramming.
Step Action Yes No
1  Perform the diagnostic system check.
Was the check performed?		 Go to Step 2  Go to Diagnostic System Check - Engine Controls
2
  1. Turn ON the ignition, with the engine OFF.
  2. Install a scan tool.
Are any additional DTCs set?		 Go to Diagnostic Trouble Code (DTC) List Go to Step 3 
3
  1. Review and record the scan tool failure records data.
  2. Operate the vehicle within failure records conditions at noted.
  3. Using the scan tool, monitor specific DTC info for DTC P1391.
Does the scan tool indicate that DTC P1391 failed?		 Go to Step 4  Go to Diagnostic Aids
4
  1. Turn OFF the ignition.
  2. Disconnect the engine control module (ECM) and inspect for an open or short in the wire between ECM connector terminal K7 and electronic brake control module (EBCM) connector terminal 25.
Is the problem found?		 Go to Step 5  Go to Step 6 
5 Repair an open or short in the wire between ECM connector terminal K7 and EBCM connector terminal 25.
Did you complete the repair?		 Go to Step 7  -
6 
  1. Turn OFF the ignition.
  2. Replace the ECM. Refer to Engine Control Module Replacement .
Is the repair complete?		 Go to Step 7  -
7
  1. Use a scan tool in order to clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the conditions for setting this DTC as supported in the text.
Does the scan tool indicate that this diagnostic ran and passed?		 Go to Step 8  Go to Step 2 
8 Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?		 Go to Diagnostic Trouble Code (DTC) List System OK
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