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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1472 (Engine Control System - Diagnosis - 4.2L (DTC P0140 To DTC P0506)) >> Diagnosis >> DTC P0201-P0206 >> Diagnostic Aids

Diagnostic Aids

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DTC P0201-P0206

Step Action Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference: Powertrain Control Module (PCM) Connector End Views  or  Engine Controls 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 data 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 fuel injector harness multi-way connector.
  3. Probe the appropriate fuel injector control circuit, PCM side, with a test lamp that is connected to battery voltage Refer to Probing Electrical Connectors in Wiring Systems.
  4. Crank the engine.
Does the test lamp flash when cranking the engine?
Go to Step 7  Go to Step 4 
4 Does the test lamp remain illuminated at all times? Go to Step 6  Go to Step 5 
5 Test the control circuit of the fuel injector for a short to voltage or for an open between the multi-way connector and the PCM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 14 
6 Test the control circuit of the fuel injector for a short to ground between the multi-way connector and the PCM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 17 
7 Inspect the accessible fuel injector jumper harness between the multi-way connector and the intake manifold for the following:
  • Poor connections at the multi-way connector
  • Damaged or pinched wiring
  • Broken wires inside the insulation

Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 8 
8 Probe the appropriate fuel injector control circuit, fuel injector side, at the multi-way connector, with a test lamp that is connected to battery voltage. Refer to Probing Electrical Connectors in Wiring Systems.
Does the test lamp illuminate?
Go to Step 15  Go to Step 9 
9 With a DMM, test for continuity between the ignition 1 voltage circuit terminal and the appropriate fuel injector control circuit terminal, at the multi-way connector. Refer to Testing for Continuity in Wiring Systems.
Does the DMM indicate OL?
Go to Step 10  Go to Step 12 
10 Test the control circuit of the fuel injector for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 11 
11 Test the ignition 1 voltage circuit of the fuel injector for an open between the fuel injector and the splice. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 13 
12 Test the control circuit of the fuel injector for a short to voltage or a short to another circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 16 
13 Test for an intermittent and for a poor connection at the affected fuel injector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 16 
14 Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 18  Go to Step 17 
15 Repair the short to ground in the fuel injector control circuit. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 18  -
16 Replace the appropriate fuel injector. Refer to Fuel Injector Replacement .
Did you complete the replacement?
Go to Step 18  -
17 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement .
Did you complete the replacement?
Go to Step 18  -
18
  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 19 
19 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