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Test Description

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The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  To set this code, the password that the PCM has learned does not agree with the password being received from the theft deterrent control module. This condition can occur if the theft deterrent control module has been replaced and the programming theft deterrent system components procedure has not been performed.
  2. 4:  If the PCM resets the DTC after the programming theft deterrent system components procedure has been performed, the theft deterrent control module is malfunctioning.
DTC P1631

Step Action Yes No
Schematic Reference: Theft Deterrent System Schematics 
Connector End View Reference: Theft Deterrent System Connector End Views 
1 Did you perform the Theft Deterrent Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Theft Deterrent 
2 
IMPORTANT: If a 10 Minute or 30 Minute Re-Learn Procedure is performed, all keys not learned at that time will be erased and will not be recognized. Perform the Adding Keys procedure on all keys or instruct the customer how to perform the Adding Keys procedure. Refer to Adding Keys (Export including Canada) .
Perform the Programming Theft Deterrent System Components procedure. Refer to Programming Theft Deterrent System Components .Is the procedure complete?		 Go to Step 3  -
3
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 Go to Step 4  System OK
4 
IMPORTANT: If a 10 Minute or 30 Minute Re-Learn Procedure is performed, all keys not learned at that time will be erased and will not be recognized. Perform the Adding Keys procedure on all keys or instruct the customer how to perform the Adding Keys procedure. Refer to Adding Keys (Export including Canada) .
  1. Replace the theft deterrent control module. Refer to Theft Deterrent Control Module Replacement .
  2. Perform the programming theft deterrent system components procedure. Refer to Programming Theft Deterrent System Components .
Is the replacement complete?		 Go to Step 5  -
5
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 Go to Step 2  System OK
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