• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
Ignition 1 Voltage | P0100 | P0100 | P0100 | -- | P0101 |
MAF Sensor Signal | P0100 | P0102 | P0100 | P0102 | P0101 |
Low Reference | -- | P0102 | P0100 | -- | P0101 |
The mass air flow (MAF) sensor is located in the air intake duct. The MAF sensor is an airflow meter that measures the amount of air that enters the engine. The MAF sensor uses a hot film that is cooled by air flowing past the sensing film as air enters the engine. The amount of cooling is proportional to the amount of the air flow. As the air flow increases, more current is required in order to maintain the hot film at a constant temperature. The engine control module (ECM) uses the MAF sensor in order to provide the correct fuel delivery for all operating conditions.
• | The engine is operating. |
• | The ignition voltage is greater than 10 volts. |
• | DTC P0100, P0102, and P0103 run continuously when the above conditions are met for 1 second. |
The ECM detects that the MAF sensor signal is 0.0 Hz.
The ECM detects that the MAF sensor signal is less than 1135 Hz.
The ECM detects that the MAF sensor signal is greater than 15,152 Hz.
DTCs P0100, P0102, and P0103 are Type B DTCs.
DTCs P0100, P0102, and P0103 are Type B DTCs.
• | Inspect the harness of the MAF sensor to verify that it is not routed too close to the following components: |
- | The secondary ignition wires or coils |
- | Any solenoids |
- | Any relays |
- | Any motors |
• | Inspect the hydro-carbon (HC) filter in the air cleaner assembly for ruptures that would leak charcoal into the air intake, contaminating the sensing element. |
• | Inspect for any contamination, water intrusion, or debris on the sensing elements of the MAF sensor. If debris is present, clean the sensor. If the sensor cannot be cleaned, replace the sensor. |
• | A high resistance may cause a driveability concern before this DTC sets. |
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
J 38522 Variable Signal Generator
Caution: Do NOT use the low reference circuit in the component harness connector for this test. Damage to the control module may occur due to excessive current draw.
⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all the components connected to the ignition circuit and replace as necessary. |
⇒ | If greater than the specified value, repair the ground circuit for an open/high resistance. |
⇒ | If less than the specified range, test the signal circuit for an open/high resistance or a short to ground. If the circuit/connections test normal, replace the ECM. |
⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit/connections test normal, replace the ECM. |
⇒ | If the parameter is not within the specified range, replace the ECM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |