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Home >> Buick >> 2007 >> Lucerne CX >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 3.8L - DTC P0350 To DTC P0607 >> DTC P0350 >> Test Description
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Test Description

The number below refers to the step number on the diagnostic table.

  1. 3:  When the low resolution engine speed signal circuit is touched with the test lamp, the PCM detects engine speed and sends timing signals on the IC timing control circuit.
DTC P0350

Step
 		 Action Values Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
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 Testing for Intermittent Conditions and Poor Connections
3 
  1. Turn OFF the ignition.
  2. Disconnect the ignition control module (ICM) connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the frequency from the ignition control (IC) timing control circuit, at the ICM connector, to a good ground with a DMM. Refer to Circuit Testing .
  5. Touch the low resolution engine speed signal circuit repeatedly at the ICM connector with a test lamp that is connected to battery voltage.
  6. Observe the DMM.
Does the frequency remain at the specified value when the circuit is touched?		 0 Hz Go to Step 5  Go to Step 4 
4 Observe the DTC Info with the scan tool.
Is DTC P1350 also set?		 - Go to Step 8  Go to Step 11 
5
  1. Connect a test lamp to battery voltage.
  2. Probe the ignition control timing control circuit at the ICM connector with the test lamp. Refer to Probing Electrical Connectors .
Does the test lamp illuminate?		 - Go to Step 9  Go to Step 6 
6
  1. Connect the test lamp to a good ground.
  2. Probe the IC timing control circuit at the ICM connector with the test lamp.
Does the test lamp illuminate?		 - Go to Step 7  Go to Step 10 
7 Test the IC timing control circuit between the ICM and the powertrain control module (PCM) for a short to voltage. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
8 Test the IC timing signal circuit between the ICM and the PCM for a short to ground. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
9 Test the IC timing control circuit between the ICM and the PCM for a short to ground. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
10 Test the IC timing control circuit between the ICM and the PCM for an open. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 12 
11 Test for an intermittent and poor connections at the ICM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 13 
12 Test for an intermittent and poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
13 Replace the ICM. Refer to Ignition Control Module Replacement .
Did you complete the replacement?		 - Go to Step 15  -
14 Replace the PCM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?		 - Go to Step 15  -
15
  1. Clear the DTCs with a scan tool.
  2. Turn OFF 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 16 
16 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 System OK
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