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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1022 (Engine Controls Diagnosis - 6.6L (Lb7) (DTCS P0612 To P2141)) >> Diagnosis >> DTC P2138 >> Conditions for Clearing the DTC

Conditions for Clearing the DTC

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
DTC P2138

Step Action Values 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
  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.
Does the DTC fail this ignition?		 - Go to Step 4  Go to Step 3 
3
  1. Select the diagnostic trouble code (DTC) option using the scan tool.
  2. Lightly touch and move the related accelerator pedal position (APP) wiring harnesses and connectors while monitoring the DTC information.
Did this DTC fail this ignition during the above test ?		 - Go to Step 4  Go to Intermittent Conditions
4 Is DTC P2139 also set? - Go to Step 6  Go to Step 5 
5 Is DTC P2140 also set? - Go to Step 12  -
6
  1. Turn OFF the ignition.
  2. Disconnect the APP sensor harness connector.
  3. Turn ON the ignition.
  4. Test for voltage at the APP sensor 2, 5-volt reference circuit with a test lamp connected to ground.
Does the test lamp illuminate?		 - Go to Step 7  Go to Step 16 
7 Connect a test lamp between the APP sensor 2, 5-volt reference circuit and the APP sensor 2 low reference circuit.
Does the test lamp illuminate?		 - Go to Step 8  Go to Step 18 
8
  1. Disconnect the test lamp.
  2. With the APP sensor harness connector still disconnected, observe the APP sensor 1 voltage parameter with a scan tool.
Is the APP sensor 1 voltage less than the specified value?		 1 V Go to Step 15  Go to Step 9 
9 Is the APP sensor 2 voltage more than the specified value? 4 V Go to Step 10  Go to Step 11 
10 Test the APP sensor 1 signal circuit for a short to the APP sensor 3 signal circuit with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 12 
11 Test the APP sensor 1 signal circuit for a short to the APP sensor 2 signal circuit with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 12 
12
  1. Turn OFF the ignition.
  2. Disconnect the APP sensor harness connector.
  3. Turn ON the ignition.
  4. Test for voltage at the APP sensor 1, 5-volt reference circuit with a test lamp connected to ground.
Does the test lamp illuminate?		 - Go to Step 13  Go to Step 19 
13 Connect the test lamp between the APP sensor 1, 5-volt reference circuit and the APP sensor 1 low reference circuit.
Does the test lamp illuminate?		 - Go to Step 14  Go to Step 20 
14
  1. Connect a fused jumper wire between the APP sensor 1 signal circuit and the APP sensor 1, 5-volt reference circuit.
  2. Observe the APP sensor 1 voltage parameter with a scan tool.
Does the scan tool indicate voltage at the specified value?		 5 V Go to Step 21  Go to Step 15 
15
  1. Turn OFF the ignition.
  2. Disconnect the engine control module (ECM) harness connector that contains the APP sensor 1 signal circuit.
  3. Test the APP sensor 1 signal circuit for high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 23 
16
  1. Turn OFF the ignition.
  2. Disconnect the ECM harness connector that contains the APP sensor 2, 5-volt reference circuit.
  3. Test the APP sensor 2, 5-volt reference circuit for high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 23 
17
  1. Turn OFF the ignition.
  2. Disconnect the ECM harness connector that contains the APP sensor 2 signal circuit.
  3. Turn ON the ignition.
  4. Test the APP sensor 2 signal circuit for high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 23 
18
  1. Turn OFF the ignition.
  2. Disconnect the ECM harness connector that contains the APP sensor 2 low reference circuit.
  3. Test the APP sensor 2 low reference circuit for resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 23 
19
  1. Turn OFF the ignition.
  2. Disconnect the ECM harness connector that contains the APP sensor 1, 5-volt reference circuit.
  3. Turn ON the ignition.
  4. Test the APP sensor 1, 5-volt reference circuit for high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 23 
20
  1. Turn OFF the ignition.
  2. Disconnect the ECM harness connector that contains the APP sensor 1 low reference circuit.
  3. Test the APP sensor 1 low reference circuit for resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 23 
21 Inspect for poor connections at the harness connector of the APP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 22 
22 Replace the APP sensor assembly. Refer to Accelerator Pedal Position (APP) Sensor Replacement .
Did you complete the replacement?		 - Go to Step 25  -
23 Inspect for poor connections at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 25  Go to Step 24 
24 Replace the ECM. Refer to Engine Control Module (ECM) Replacement .
Did you complete the replacement?		 - Go to Step 25  -
25
  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 26 
26 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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