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Diagnostic Aids

DTC P1640: Control Module Output A Circuit

Step Action Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Controls Connector End Views  or  Powertrain Control Module (PCM) Connector End Views 
1 Did you perform the Diagnostic System Check - Vehicle? Go to Step 2  Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2 Is DTC P0560 set? Go to DTC P0560 in Engine Electrical Go to Step 3 
3 Observe the Output Driver Data List with a scan tool.
Do any parameters indicate a fault present?
Go to Step 4  Go to Step 5 
4 Test for a short to voltage on the control circuit of the component that indicated a fault. Refer to Testing for a Short to Voltage in Wiring Systems.
Did you find and correct the condition?
Go to Step 6  Go to Step 5 
5 Replace the powertrain control module (PCM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the replacement?
Go to Step 6  -
6
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Does the DTC fail this ignition?
Go to Step 2  Go to Step 7 
7 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?
Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information System OK