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Home >> Cadillac >> 2004 >> CTS Base, 3.6 7 >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 13 (Engine Controls - 2.6L & 3.2L - Diagnosis (DTC P0172 - P0446)) >> Diagnostic Trouble Codes >> DTC P0261, P0264, P0267, P0270, P0273, or P0276 >> Test Description

Test Description

WARNING: This page is about a different variant/trim than selected.

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

  1. 2:  This step verifies that the condition is present.
  2. 4:  This step isolates the condition. If the test lamp is illuminated the fuel injector control circuit is shorted to ground between the multi-way connector and the ECM.
  3. 5:  This step tests for a short to ground in the fuel injector control circuit between the multi-way connector and the affected fuel injector.
  4. 6:  This step isolates the circuit between the multi-way connector and the ECM.
  5. 7:  This step inspects for fuel injector harness damage between the multi-way connector and the intake plenum. Careful inspection may isolate the condition before removal of the intake plenum.
DTC P0261, P0264, P0267, P0270, P0273, or P0276

Step Action Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Control Module (ECM) 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 
IMPORTANT: If DTCs P0261, P0264, P0267, P0270, P0273 and P0276 are all set, inspect ignition 1 voltage supply circuit for a short to ground.
  1. Clear the DTCs with a scan tool.
  2. Attempt to start the engine.
Does a fuel injector DTC set?		 Go to Step 4  Go to Step 3 
3
  1. Observe the Freeze Frame/Failure records data for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Attempt to 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 4  Go to Diagnostic Aids
4 
  1. Turn OFF the ignition.
  2. Disconnect the fuel injector harness multi-way connector.
  3. Probe the affected fuel injector control circuit, engine control module (ECM) side, with a test lamp connected to B+.
  4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?		 Go to Step 6  Go to Step 5 
5  With the test lamp still connected to B+, probe the affected fuel injector control circuit, fuel injector harness side.
Does the test lamp illuminate?		 Go to Step 7  Go to Intermittent Conditions
6  Test the control circuit of the affected fuel injector for a short to ground between the multi-way connector and the ECM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 13  Go to Step 10 
7 
  1. Inspect the accessible fuel injector jumper harness between the multi-way connector and the intake plenum for the following:
    • Damaged or pinched wiring
    • Broken wires inside the insulation
  2. Repair as necessary. Refer to Wiring Repairs and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 13  Go to Step 8 
8
  1. Remove the upper intake. Refer to Intake Plenum Replacement in Engine Mechanical.
  2. Test the control circuit of the fuel injector for a short to ground between the multi-way connector and the affected fuel injector connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 13  Go to Step 9 
9 Test for an intermittent and for a poor connections at the harness connector of the appropriate 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 13  Go to Step 11 
10 Test for an intermittent and for a poor connections at the harness connector of the ECM. 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 13  Go to Step 12 
11 Replace the affected fuel injector. Refer to Fuel Injectors and Fuel Rail Replacement .
Did you complete the replacement?		 Go to Step 13  -
12 Replace the ECM. Refer to Engine Control Module (ECM) Replacement .
Did you complete the replacement?		 Go to Step 13  -
13
  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 14 
14 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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