Possible causes – Faulty Intake Air Temperature (IAT) sensor– Dirty air filter– Intake Air Temperature (IAT) sensor harness is open or shorted– Intake Air Temperature (IAT) sensor circuit poor electrical connection When is the code detected? – An excessively high

Possible causes – Faulty Intake Air Temperature (IAT) sensor– Dirty air filter– Intake Air Temperature (IAT) sensor harness is open or shorted– Intake Air Temperature (IAT) sensor circuit poor electrical connection When is the code detected? An excessively low or

Possible causes – Faulty Intake Air Temperature (IAT) sensor– Dirty air filter– Intake Air Temperature (IAT) sensor harness is open or shorted– Intake Air Temperature (IAT) sensor circuit poor electrical connection When is the code detected? An excessively low voltage

Possible causes – Faulty Intake Air Temperature (IAT) sensor– Intake Air Temperature (IAT) sensor harness is open or shorted– Intake Air Temperature (IAT) sensor electrical circuit poor connection Tech notes If the Intake Air Temperature (IAT) is part of the

Possible causes – Faulty Intake Manifold Tuning Valve (IMTV)– Intake Manifold Tuning Valve harness is open or shorted– Intake Manifold Tuning Valve circuit poor electrical connection When is the code detected? The Engine Control Module (ECM) has detected an improper

Possible causes – Faulty knock sensor– Knock sensor circuit poor electrical connection– Knock sensor harness is open or shorted– Faulty Engine Control Module (ECM) Tech notes The P0330 code means that the Knock Sensor is not working properly. Problems with

Possible causes – Faulty Low Speed Radiator Fan Relay– Low Speed Radiator Fan Relay harness is open or shorted– Low Speed Radiator Fan Relay circuit poor electrical connection– Faulty Electric Fan– Faulty Front Control Module (FCM) Symptoms – Engine Light

Possible causes – Faulty Manifold Absolute Pressure (MAP) sensor– Manifold Absolute Pressure (MAP) sensor harness open or shorted– Manifold Absolute Pressure (MAP) sensor circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P0129 JEEP

Possible causes – Faulty Manifold Absolute Pressure sensor– Manifold Absolute Pressure harness is open or shorted– Manifold Absolute Pressure sensor circuit poor electrical connection– Faulty Engine Control Module (ECM) When is the code detected? Map sensor input voltage is below

Possible causes – Faulty Manifold Absolute Pressure sensor– Manifold Absolute Pressure harness is open or shorted– Manifold Absolute Pressure sensor circuit poor electrical connection– Faulty Engine Control Module (ECM) When is the code detected? An excessively low or high voltage

Possible causes – Faulty Manifold Absolute Pressure sensor– Manifold Absolute Pressure harness is open or shorted– Manifold Absolute Pressure sensor circuit poor electrical connection– Faulty Engine Control Module (ECM) When is the code detected? Manifold Absolute Pressure (MAP) sensor input

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty mass air flow sensor– Intake air leaks– Dirty mass air flow sensor– Dirty mass air filter– Mass air flow sensor harness is open or shorted– Mass air flow sensor circuit poor electrical connection Tech notes Before

Possible causes – Faulty overdrive off switch– Overdrive off switch harness or connectors– Overdrive off switch circuit is open or shorted When is the code detected? The P0751 code is detected when the Over Drive (O/D) switch value has not

Possible causes – Faulty Park/Neutral Position Switch– Misadjusted Park/Neutral Position Switch– Park/Neutral Position Switch harness is open or shorted– Park/Neutral Position Switch circuit poor electrical connection When is the code detected? The transmission range switch detects the selector lever position

Possible causes – Faulty Park/Neutral Switch– Park/Neutral Switch harness is open or shorted– Park/Neutral Switch circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Possible causes – Faulty Power Steering Pressure Sensor– Power Steering Pressure Sensor harness is open or shorted– Power Steering Pressure Sensor circuit poor electrical connection When is the code detected? A low voltage from the Power Steering Pressure Sensor is

Possible causes – Faulty Power Steering Pressure Sensor– Power Steering Pressure Sensor harness is open or shorted– Power Steering Pressure Sensor circuit poor electrical connection When is the code detected? An out of range voltage from the Power Steering Pressure