P0337
Crankshaft Position Sensor A Circuit Low Input
If your code reader dashboard displays the generic DTC error code P0337, your vehicle is currently experiencing an active failure related to "Crankshaft Position Sensor A Circuit Low Input". Proper system troubleshooting is required to safely clear this warning.
Driver's Summary
P0337 is triggered when the PCM detects an abnormal condition associated with crankshaft position sensor a circuit low input. Typical symptoms include engine cranks but will not start, stalling, no tachometer signal. Given the high severity of this code, continuing to drive risks significant mechanical damage. Have it diagnosed immediately.
Symptoms
Engine cranks but will not start, stalling, no tachometer signal
Common Causes
- Short to ground in crank sensor wiring
- Failed crankshaft position sensor
- Dead battery
- Bad PCM
How to Fix
- 1 Trace and repair shorted wire
- 2 Replace crankshaft position sensor
- 3 Test and charge battery
- 4 Test PCM
Technical Explanation
Code P0337 is confirmed when the ECM's diagnostic algorithm detects a parameter deviation that persists across a defined number of consecutive drive cycles. For injector-specific codes, the ECM monitors the injector control circuit voltage drop during each pulse; a shorted or open injector presents a characteristic resistance signature that differs measurably from a healthy unit. The MIL illuminates after the fault is confirmed on two consecutive drive cycles, and the freeze frame data captured at first detection is stored in the PCM's memory for diagnostic reference.
Is It Safe to Drive?
An active P0337 code under high-severity conditions means the affected system is operating outside safe parameters. Continued driving — especially under load or at highway speeds — significantly increases the risk of secondary damage to components like failed crankshaft position sensor.
Mechanic's Pro Tip
Module replacement should always be the last resort for P0337 after exhaustively verifying all power supply circuits, ground connections, and communication bus wiring. Use a wiring diagram to locate all fuses, relays, and ground points for the affected module, and measure voltage drop on each ground with the circuit loaded. A module "failure" is frequently a corroded ground eyelet or a weak battery causing brownout conditions — fix these first and you'll save hundreds of dollars on an unnecessary module replacement.
Related Fault Codes
Frequently Asked Questions
What does OBD2 code P0337 mean?
OBD2 code P0337 refers to Crankshaft Position Sensor A Circuit Low Input. If your code reader dashboard displays the generic DTC error code P0337, your vehicle is currently experiencing an active failure related to "Crankshaft Position Sensor A Circuit Low Input". Proper system troubleshooting is required to safely clear this warning.
What are the most common symptoms of DTC P0337?
Drivers experiencing code P0337 typically report: Engine cranks but will not start, stalling, no tachometer signal.
Is it safe to drive with trouble code P0337 active?
An active P0337 code under high-severity conditions means the affected system is operating outside safe parameters. Continued driving — especially under load or at highway speeds — significantly increases the risk of secondary damage to components like failed crankshaft position sensor.
How much does it cost to fix code P0337?
The estimated repair cost for P0337 ranges from $100 to $400 USD. Crank sensor replacement: 150 - 350
Crank sensor replacement: 150 - 350
Need Professional Diagnostic Assistance?
Always verify sensor signals and wiring integrity with an OBD2 scanner before purchasing replacement parts.
Explore All Powertrain Codes →