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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1070 (Engine Controls Diagnosis - 6.6L (Lb7) (DTCS P0237 To P0611)) >> Diagnosis >> DTC P0335 >> Conditions for Clearing the MIL/DTC

Conditions for Clearing the MIL/DTC

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DTC P0335

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 Attempt to start the engine.
Does the engine start and run?
- Go to Intermittent Conditions Go to Step 3 
3
  1. Turn OFF the ignition.
  2. Disconnect the crankshaft position (CKP) sensor harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the 12-volt reference of the CKP sensor to a good ground with a DMM.
Is the voltage within the specified value?
B+ Go to Step 4  Go to Step 8 
4 Measure the voltage from the 12-volt reference to the low reference of the CKP sensor with a DMM.
Is the voltage within the specified value?
B+ Go to Step 5  Go to Step 7 
5 Connect a DMM between the CKP sensor signal and a good ground.
Does the DMM display more than the specified value?
1 V Go to Step 9  Go to Step 6 
6
  1. Turn OFF the ignition.
  2. Reconnect the CKP sensor.
  3. Disconnect the engine control module (ECM) connectors.
  4. Carefully remove the CKP signal circuit pin from the ECM connector. Refer to Push to Seat Connectors in Wiring Systems.
  5. Reconnect the ECM connectors.
  6. Connect a DMM between the CKP signal circuit pin at the ECM and a good ground.
  7. Crank the engine and measure the DC duty cycle of the CKP signal.
Does the DMM display a DC duty cycle within the specified value?
45-55% Go to Step 12  Go to Step 10 
7 Test the low reference circuit for an open. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 17  Go to Step 12 
8 Test the 12-volt reference circuit for an open or a short to ground. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 17  Go to Step 12 
9 Test the CKP signal circuit for a short to voltage or a short to the 12-volt reference circuit. Refer to Testing for a Short to Voltage and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 17  Go to Step 15 
10 Test the CKP signal circuit for an open or a short to ground. Refer to Testing for Continuity , Testing for Short to Ground and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 17  Go to Step 11 
11 Check for poor connections at the CKP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 17  Go to Step 13 
12 Check for poor connections at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 17  Go to Step 15 
13
  1. Remove the CKP sensor. Refer to Crankshaft Position (CKP) Sensor Replacement .
  2. Visually inspect the CKP sensor for the following conditions:
    • Physical damage
    • Loose or improper installation
    • Wiring routed too closely to secondary ignition components
  3. The following conditions may cause this DTC to set:
    • Excessive air gap between the CKP sensor and the reluctor wheel
    • Electromagnetic interference in the CKP sensor circuits
    • Foreign material passing between the CKP sensor and the reluctor wheel
    • Insufficient fuel
Did you find and correct the condition?
- Go to Step 17  Go to Step 14 
14 Inspect the CKP reluctor wheel for the following conditions:
  • Physical damage
  • Improper installation
  • Excessive endplay or looseness

Refer to Crankshaft Reluctor and Oil Pump Drive Gear Replacement in Engine Mechanical-6.6L.
Did you find and correct the condition?
- Go to Step 17  Go to Step 16 
15 Replace the ECM. Refer to Engine Control Module (ECM) Replacement .
Did you complete the replacement?
- Go to Step 17  -
16 Replace the CKP sensor. Refer to Crankshaft Position (CKP) Sensor Replacement .
Did you complete the replacement?
- Go to Step 17  -
17
  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 18 
18 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