DTC P0337. Chevrolet Epica 2005

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2005 🢒 Epica 🢒 Engine 🢒 Engine Controls - 2.5L (LBK) 🢒 DTC P0337

Circuit 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 consists of the following circuits:

•	A CKP sensor high reference

•	A CKP sensor low reference

•	A shielded ground

If the ECM detects less than 58 reference pulses, this DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0337 Crankshaft Position (CKP) Sensor Circuit Low Duty Cycle

Conditions for Running the DTC

•	The engine is cranking or running.

•	DTC P0337 runs continuously once the above conditions are met.

Conditions for Setting the DTC

The ECM detects less than 58 reference pulses for 10 consecutive crankshaft revolutions.

Action Taken When the DTC Sets

•	The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

•

The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores the information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

•	The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.

•	A current DTC, Last Test Failed, clears when the diagnostic runs and passes.

•	A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

•	Clear the MIL and the DTC with a scan tool.

Test Description

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

This step determines if the condition is current.

This step tests for an internal condition within the CKP sensor.

This step tests if the CKP sensor is capable of generating a signal.

The ECM supplies 1.8 volts to the CKP sensor circuit. If the voltage is not within range, this indicates there is a circuit or ECM condition.

This step is testing if the signal circuit and the low reference circuits of the CKP sensor are shorted together. If the DMM displays continuity, the circuits are shorted together.

Step

Action

Values

Yes

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Engine Control Module Connector End Views

Did you perform the Diagnostic System Check - Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

Attempt to start the engine.
Observe the DTC Info with a scan tool.

Does DTC P0337 fail this ignition?

Go to Step 4

Go to Step 3

Observe the Freeze Frame/Failure Records for this DTC.
Turn OFF the ignition for 30 seconds.
Start the engine.
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 Intermittent Conditions

Turn OFF the ignition.
Disconnect the crankshaft position (CKP) sensor.
Measure the resistance between thehigh reference and the low reference circuits of the CKP sensor with a DMM.

Is the resistance within the specified range?

460-620 ohms

Go to Step 5

Go to Step 11

Connect a DMM between the high reference and the low reference circuits of the CKP sensor.
Set the DMM to the AC voltage scale.
Crank the engine.
Observe the DMM while the engine is cranking.

Is the voltage more than the specified value while the engine is cranking?

1.4 ACV

Go to Step 6

Go to Step 14

Turn ON the ignition, with the engine OFF.
Set the DMM to the DC voltage scale.
Measure the voltage between the high reference circuit of the CKP sensor and a good ground with a DMM.

Is the voltage within the specified range?

1.5-2.0 DCV

Go to Step 7

Go to Step 9

Measure the voltage between the low reference circuit of the CKP sensor and a good ground with a DMM.

Is the voltage within the specified range?

1.5-2.0 DCV

Go to Step 8

Go to Step 10

Turn OFF the ignition.
Disconnect the engine control module (ECM).
Measure the resistance between the high reference and the low reference circuits of the CKP sensor at the ECM harness connector.

Does the DMM display OL?

Go to Step 13

Go to Step 15

Test the high reference circuit of the CKP sensor for the following:

•

An open

•	A short to ground

•	A short to voltage

•	High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 12

Test the low reference circuit of the CKP sensor for the following :

•

An open

•	A short to ground

•	A short to voltage

•	High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 12

Test for an intermittent and for a poor connection at the CKP sensor. 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 18

Go to Step 16

Test for an intermittent and for a poor connection at 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 18

Go to Step 17

Test for an intermittent and for a poor connection at the CKP sensor. 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 18

Go to Step 17

Important: If the sensor lead is damaged in any way, DO NOT repair the lead.

Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement .
Inspect the CKP sensor for the following conditions:

•	Physical damage

•	Excessive play or looseness

•	Improper installation

•	Foreign material passing between the CKP sensor and the reluctor wheel

•	Excessive air gap between the CKP sensor and the reluctor wheel

Did you find and correct the condition?

Go to Step 18

Go to Step 16

Repair the short between the high reference circuit of the CKP sensor and the low reference circuit of the CKP sensor.

Did you complete the repair?

Go to Step 18

Replace the CKP sensor. Refer to Crankshaft Position Sensor Replacement .

Did you complete the replacement?

Go to Step 18

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the replacement?

Go to Step 18

Clear the DTCs with a scan tool.
Turn OFF the ignition for 30 seconds.
Start the engine.
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 19

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