GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2006 🢒 Optra - Mexico 🢒 Engine 🢒 Engine Controls - 1.8L (L79) 🢒 DTC P0337

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptors

DTC P0337: Crankshaft Position (CKP) Sensor Circuit

Circuit/System Description

The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor produces an AC voltage of different amplitude and frequency. The frequency depends on the velocity of the crankshaft, and the AC voltage output depends on the crankshaft position and battery voltage. The CKP sensor works in conjunction with a 58X reluctor wheel attached to the crankshaft. The engine control module (ECM) can synchronize the ignition timing, fuel injector timing, and spark knock control based on the CKP and the camshaft position (CMP) sensor inputs. The CKP sensor is also used to detect misfire and tachometer display. The CKP sensor circuits are connected directly to the ECM. The circuits between the CKP sensor and the ECM consist of the following circuits:

    • The CKP sensor signal
    • The low reference
    • The shielded ground

Conditions for Running the DTC

P0337

    • DTCs P0341 and P0342 are not set.
    • The engine is cranking.
    • The manifold absolute pressure (MAP) does not change more than 0.6 volt or 1.2 kPa for a manual transmission or 1.2 volts or 0.8 kPa for an automatic transmission during crank.
    •  The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM does not detect a signal from the CKP sensor.

Action Taken When the DTC Sets

DTC P0337 is a Type A DTC.

Conditions for Clearing the DTC

DTC P0337 is a Type A DTC.

Diagnostic Aids

The following conditions could also set the DTCs:

    • Physical damage to the CKP sensor or the reluctor wheel
    • Excessive play or looseness of the CKP sensor or the reluctor wheel
    • Improper installation of the CKP sensor or the reluctor wheel
    • Foreign material passing between the CKP sensor and the reluctor wheel
    • Excessive air gap between the CKP sensor and the reluctor wheel

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Control Module Connector End Views
    •  Engine Controls Connector End Views

Description and Operation:

Electronic Ignition (EI) System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Circuit/System Verification
  1. Attempt to start the engine. Observe the scan tool DTC information parameter. DTC P0337 should not set.
  2. Move related harnesses/connectors of the CKP sensor and verify the engine does not stumble, stall, or change engine speed.
  3. If the vehicle passes the Circuit/System Verification test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

    Important: If the CKP sensor lead is damaged in any way, replace the CKP sensor.

  1. Ignition OFF, disconnect the harness connector of the CKP sensor.
  2. Ignition ON, verify that 2-3 volts is available on the signal circuit and the low reference circuit.
    3. ⇒If less than the specified range, test the applicable circuit for a short to ground or an open/high resistance. If the circuits/connections test normal, replace the ECM.
    ⇒If more than the specified range, test the applicable circuit for a short to voltage. If the circuits/connections test normal, replace the ECM.
  3. If all circuits/connections test normal, test or replace the CKP sensor.

Component Testing
  1. Ignition OFF, disconnect the harness connector of the CKP sensor.

    2. Important: If the CKP sensor lead is damaged in any way, replace the CKP sensor.

  2. Connect a DMM between the signal circuit and the low reference circuit of the CKP sensor.
  3. Test for 500-700 ohms between the signal circuit and low reference circuit.
    4. ⇒If not within the specified range, replace the CKP sensor.
  4. Disconnect the fuel pump relay.
  5. Set the DMM to the AC voltage scale.
  6. While cranking the engine, test for more than 1.0 ACV between the signal circuit and low reference circuit.
    7. ⇒If less than the specified range, replace the CKP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Crankshaft Position Sensor Replacement
    •  Control Module References for ECM replacement, setup, and programming