Engine Control: SFI System
1UR-FE ENGINE CONTROL: SFI SYSTEM: P0335,P0337-P0339: Crankshaft Position Sensor "A" Circuit
DESCRIPTION
The crankshaft position sensor system consists of a crankshaft angle sensor rotor and Magneto resistance Element (MRE) type sensor. The crankshaft angle sensor rotor has 34 teeth at 10° intervals (2 teeth are missing for detecting top dead center), and is installed to the rear end of the crankshaft. The crankshaft position sensor generates 34 signals per crankshaft revolution. The ECM uses the G2 signal to distinguish between the cylinders, and uses the NE signal to detect the crankshaft position and engine speed.
- Reference: Inspection using an oscilloscope.
Standard:
HINT
G2 is the camshaft position sensor signal, and NE is the crankshaft position sensor signal.
MONITOR DESCRIPTION
If there is no signal from the crankshaft position sensor despite the crankshaft revolving, the ECM interprets this as a malfunction of the sensor.
When the sensor output voltage remains at below 0.3 V, or higher than 4.7 V for more than 4 seconds, the ECM stores a DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
P0335
P0335: Crankshaft Position Sensor Range Check
Case 1
Case 2
P0337, P0338 Crankshaft Position Sensor Range Check (Low Voltage, High Voltage)
TYPICAL MALFUNCTION THRESHOLDS
P0335 Crankshaft Position Sensor Range Check
P0337 Crankshaft Position Sensor Range Check (Low Voltage)
P0338 Crankshaft Position Sensor Range Check (High Voltage)
COMPONENT OPERATING RANGE
CONFIRMATION DRIVING PATTERN
- Connect the Techstream to the DLC3.
- Turn the engine switch on (IG) and turn the Techstream on.
- Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
- Turn the engine switch off and wait for at least 30 seconds.
- Turn the engine switch on (IG) and turn the Techstream on.
- Start the engine.
- Idle the engine for 20 seconds or more [A].
- Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [B].
- Read the pending DTCs.
HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
- Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
- Input the DTC: P0335, P0337 or P0338.
- Check the DTC judgment result.
HINT
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [A] through [B] again.
- If no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.
HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
- If no problem is found by this diagnostic troubleshooting procedure, check for problems by referring to the engine mechanical section.
- The engine speed can be checked by using the Techstream. To perform the check, follow the procedures below:
* Connect the Techstream to the DLC3.
* Start the engine.
* Turn the Techstream on.
* Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Engine Speed.
* The engine speed may be indicated as zero despite the engine running normally. This is caused by a lack of NE signals from the crankshaft position sensor. Alternatively, the engine speed may be indicated as lower than the actual engine speed if the crankshaft position sensor output voltage is insufficient.
- Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. READ VALUE USING TECHSTREAM (ENGINE SPEED)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Engine Speed.
(e) Start the engine.
(f) Read the values displayed on the Techstream while the engine is running.
Standard:
Correct values are displayed.
HINT
- To check the engine speed change, display the graph on the Techstream.
- If the engine does not start, check the engine speed while cranking.
- If the engine speed indicated on the Techstream remains zero (0), there may be an open or short in the Crankshaft Position sensor circuit.
NG -- INSPECT CRANKSHAFT POSITION SENSOR (SENSOR POWER SOURCE)
OK -- CHECK FOR INTERMITTENT PROBLEMS
2. INSPECT CRANKSHAFT POSITION SENSOR (SENSOR POWER SOURCE)
(a) Disconnect the crankshaft position sensor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
NG -- CHECK HARNESS AND CONNECTOR (CRANKSHAFT POSITION SENSOR - ECM)
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (CRANKSHAFT POSITION SENSOR - ECM)
(a) Disconnect the crankshaft position sensor connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK SENSOR INSTALLATION (CRANKSHAFT POSITION SENSOR)
(a) Check the crankshaft position sensor installation.
OK:
Sensor is installed correctly.
NG -- SECURELY REINSTALL SENSOR Installation
OK -- Continue to next step.
5. INSPECT CRANKSHAFT ANGLE SENSOR ROTOR (TEETH OF SENSOR ROTOR)
(a) Check the teeth of the sensor rotor.
OK:
Sensor rotor does not have any cracks or deformation.
NG -- REPLACE CRANKSHAFT ANGLE SENSOR ROTOR
OK -- Continue to next step.
6. REPLACE CRANKSHAFT POSITION SENSOR
(a) Replace the crankshaft position sensor Removal.
NEXT -- Continue to next step.
7. CHECK WHETHER DTC OUTPUT RECURS (DTC P0335, P0337, P0338 AND/OR P0339)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear DTCs DTC Check / Clear.
(e) Start the engine.
(f) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(g) Read DTCs.
Result
HINT
If the engine does not start, replace the ECM.
B -- REPLACE ECM Removal
A -- END
8. CHECK HARNESS AND CONNECTOR (CRANKSHAFT POSITION SENSOR - ECM)
(a) Disconnect the crankshaft position sensor connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM Removal