DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC

Description

System Normal

Oxygen Sensor Circuit

Coolant (Water) Temp Sensor (WTS) Indication Low

Coolant (Water) Temp Sensor (WTS) Indication High

Throttle Position Sensor Circuit Indication High

Throttle Position Sensor Circuit Indication Low

Air Temp Sensor (ATS) Circuit Indication Low

Vehicle Speed Sensor

Air Temp Sensor (ATS) Circuit Indication High

Pressure Sensor (PS) Circuit Voltage High

Pressure Sensor (PS) Circuit Voltage Low

41 ⁽¹⁾

No Ignition Signal

Crank Angle Sensor

44 ⁽²⁾

Idle Switch Circuit Open Or Misadjusted

45 ⁽²⁾

Idle Switch Circuit Open Or Misadjusted

51 ⁽³⁾

EGR System Circuit Check

53 ⁽²⁾⁽³⁾

ECM Ground Circuit Check

54 ⁽²⁾⁽⁴⁾

Gear Position (5Th Switch) Circuit Grounded

71 ⁽³⁾⁽⁵⁾

Test Switch Circuit

⁽¹⁾	To check code when engine fails to start, crank engine, then with ignition still on, install fuse in diagnostic terminal of fuse block.

⁽²⁾	When code occurs, ECM will not activate CHECK ENGINE light while engine is running. When problem is fixed, memory of defective area will be erased from ECM.

⁽³⁾	Applicable to California models only.

⁽⁴⁾	Not applicable to California models.

⁽⁵⁾	Circuit is grounded for 5 seconds when driving at least 25 MPH.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Diagnostic Trouble Code Definitions