Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Chevrolet >> 2006 >> Avalanche 2500 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 8.1L - DTC P0172 To DTC P0496 >> DTC P0335 >> Test Description

Test Description

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

  1. 3:  This step determines if the fault is present.
  2. 6:  This step simulates a CKP sensor signal to the PCM. If the PCM receives the signal, the fuel pump will operate for about two seconds.
DTC P0335

Step Action Values 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 - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2 Does the engine start and continue to run? - Go to Step 3  Go to Step 4 
  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 4  Go to Testing for Intermittent Conditions and Poor Connections
4
CAUTION: Before proceeding, remove the fuses for the ignition coil and fuel injector feed circuits in order to prevent personal injury from engine rotation, sparks, and excessive engine fueling.
    IMPORTANT: An internally shorted CAM sensor can cause DTC P0335 to set. Test this circuit for a short before proceeding with this diagnostic table. Refer to Circuit Testing and Wiring Repairs .
  1. Turn ON the ignition, with the engine OFF.
  2. Disconnect the crankshaft position (CKP) sensor harness connector.
  3. Measure the voltage from the CKP sensor 12-volt reference circuit to a good ground with the DMM.
Does the DMM display the specified value?
B+ Go to Step 5  Go to Step 7 
5 Measure the voltage between the CKP sensor 12-volt reference circuit and the CKP sensor low reference circuit with the DMM.
Does the DMM display the specified value?
B+ Go to Step 6  Go to Step 8 
Momentarily connect the test lamp between the CKP sensor signal circuit and the CKP sensor 12-volt reference circuit.
Does the fuel pump operate when voltage was applied to the CKP sensor signal circuit?
- Go to Step 11  Go to Step 9 
7 Test for an open or a short to ground in the CKP sensor 12-volt reference circuit. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
- Go to Step 16  Go to Step 14 
8 Test for an open or for high resistance in the CKP sensor low reference circuit. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
- Go to Step 16  Go to Step 14 
9 Test the CKP sensor signal circuit for the following conditions:
  • High resistance
  • An open
  • A short to ground or low reference
  • A short to voltage or 12-volt reference

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 16  Go to Step 10 
10 Inspect for poor connections at the CKP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals .
Did you find and correct the condition?
- Go to Step 16  Go to Step 14 
11
  1. Remove the CKP sensor. Refer to Crankshaft Position (CKP) Sensor Replacement .
  2. Visually inspect the CKP sensor for the following conditions:
    • Excessive play or looseness
    • Excessive air gap between the CKP sensor and the reluctor wheel
    • Physical damage
    • Foreign material passing between the CKP sensor and the reluctor wheel
    • Improper installation
    • Electromagnetic interference in the CKP sensor circuits

      Refer to Wiring Repairs .

Did you find and correct the condition?
- Go to Step 16  Go to Step 12 
12 Inspect the CKP reluctor wheel for the following conditions:
Did you find and correct the condition?
- Go to Step 16  Go to Step 13 
13 Replace the CKP sensor. Refer to Crankshaft Position (CKP) Sensor Replacement .
Did you complete the repair?
- Go to Step 16  -
14 Inspect for poor connections at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you complete the repair?
- Go to Step 16  Go to Step 15 
15 Replace the PCM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?
- Go to Step 16  -
16
  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 run and pass?
- Go to Step 17  Go to Step 2 
17 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