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Home >> Oldsmobile >> 2004 >> Bravada AWD >> Repair and Diagnosis >> Electrical >> Charging Systems >> Battery, Charging System And Starting System >> Diagnostic Information and Procedures >> DTC P0621: Generator L-Terminal Circuit >> Test Description
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Test Description

DTC P0621

Step Action Yes No
Schematic Reference: Starting and Charging Schematics 
Connector End View Reference:  Engine Electrical Connector End Views  
1 Did you perform the Engine Electrical Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Engine Electrical 
2
  1. Install a scan tool.
  2. Start the engine.
  3. With a scant tool, monitor the DTC information for DTC P0621 in Engine Controls.
Does the scan tool indicate that DTC P0621 has passed?		 Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3 Test the generator turn on signal circuit for a short or open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 6  Go to Step 4 
4 Inspect for poor connections at the harness connector of the PCM. Refer to Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 6  Go to Step 5 
5 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement in Engine Controls - 4.2L.
Did you compete the replacement?		 Go to Step 6  -
6
  1. Review and record the scan tool Fail Records data.
  2. Clear any DTCs.
  3. Operate the vehicle within the Fail Records conditions as noted.
  4. Using a scan tool, monitor the Specific DTC info for this DTC.
Does the scan tool indicate that this DTC failed this ignition?		 Go to Step 2  System OK
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