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Home >> Buick >> 2004 >> Century Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (DTC P0030 To P0138) >> Engine Controls Diagnosis >> DTC P0103 >> Test Description
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Test Description

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

  1. 3:  This step tests for Electromagnetic Interference (EMI) on the signal circuit of the MAF sensor. A frequency reading with the MAF sensor disconnected may indicate an EMI related fault or a poor connection at the PCM. Disconnecting the MAF sensor may set additional related DTCs.
  2. 4:  This step will determine if incorrect harness routing has caused this DTC to set.
  3. 5:  This step will determine if water intrusion has caused this DTC to set.
DTC P0103

Step Action Values 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-Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
2
  1. Observe the Freeze Frame/Failure Records for this DTC.
  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.
Did the DTC fail this ignition?		 - Go to Step 3  Go to Diagnostic Aids
3 
  1. Turn OFF the ignition.
  2. Disconnect the MAF sensor.
  3. Start the engine.
  4. Observe the MAF sensor parameter with a scan tool.
Is the MAF sensor parameter more than the specified value?		 0 Hz Go to Step 4  Go to Step 5 
4 
  1. Turn OFF the ignition.
  2. Inspect the harness of the MAF sensor for incorrect routing that is too close to the following components:
    • The secondary ignition wires or the coils
    • Any solenoids
    • Any relays
    • Any motors
Did you find and correct the condition?		 - Go to Step 10  Go to Step 7 
5 
  1. Turn OFF the ignition.
  2. Inspect the air induction system for any water intrusion.
Did you find and correct the condition?		 - Go to Step 10  Go to Step 6 
6 Test for an intermittent and for a poor connection at the MAF sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 10  Go to Step 8 
7 Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 10  Go to Step 9 
8 Replace the MAF sensor. Refer to Mass Air Flow (MAF) Sensor Replacement .
Did you complete the replacement?		 - Go to Step 10  -
9 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement .
Did you complete the replacement?		 - Go to Step 10  -
10
  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.
Did the DTC fail this ignition?		 - Go to Step 2  Go to Step 11 
11 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List System OK
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