Dtc P0100 Mass Or Volume Air Flow Circuit
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
READ VALUE USING MASS AIR FLOW METER (MAF)
INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE)
INSPECT MASS AIR FLOW METER (VG VOLTAGE)
CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
INSPECT FUSE (EFI NO. 3)
CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ENGINE ROOM JUNCTION BLOCK)
INSPECT ENGINE ROOM JUNCTION BLOCK (EFI RELAY)
CHECK HARNESS AND CONNECTOR (SENSOR GROUND)
CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
DTC P0100 Mass or Volume Air Flow Circuit |
DTC P0102 Mass or Volume Air Flow Circuit Low Input |
DTC P0103 Mass or Volume Air Flow Circuit High Input |
DESCRIPTION
The Mass Air Flow (MAF) meter is a sensor that measures the amount of air flowing through the valve.The ECM uses this information to determine the fuel injection time and to prove appropriate air-fuel ratio.Inside the MAF meter, there is a heated platinum wire which is exposed to the flow of intake air.By applying a specific electrical current to the wire, the ECM heats it to a given temperature. The flow of incoming air cools both the wire and an internal thermistor, affecting their resistance. To maintain a constant current value, the ECM varies the voltage applied to these components in the MAF meter. The voltage level is proportional to the airflow through the sensor, and the ECM uses it to calculate the intake air volume.The circuit is constructed so that the platinum hot wire and the temperature sensor provide a bridge circuit, and the power transistor is controlled so that the potentials of A and B remain equal to maintain the predetermined temperature.- HINT:
- When any of these DTCs are set, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is calculated by the ECM, according to the engine RPM and throttle valve position. Fail-safe mode continues until a pass condition is detected.
DTC No.
| DTC Detection Condition
| Trouble Area
|
P0100
| Open or short in Mass Air Flow (MAF) meter circuit for 3 seconds
| - Open or short in MAF meter circuit
- MAF meter
- ECM
|
P0102
| Open in Mass Air Flow (MAF) meter circuit for 3 seconds
| - Open in MAF meter circuit
- Short in MAF meter circuit
- MAF meter
- ECM
|
P0103
| Short in Mass Air Flow (MAF) meter circuit for 3 seconds
| - Short in MAF meter circuit (+B circuit)
- MAF meter
- ECM
|
- HINT:
- When any of these DTCs are set, check the air-flow rate by entering the following menus on the intelligent tester: Powertrain / Engine / Data List / MAF.
Mass Air Flow Rate (gm/s)
| Malfunctions
|
Approximately 0.0
| - Open in Mass Air Flow (MAF) meter power source circuit
- Open or short in VG circuit
|
271.0 or more
| Open in EVG circuit
|
WIRING DIAGRAM
INSPECTION PROCEDURE
- HINT:
- Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction (CAMRY_ACV40 RM000000PDS01FX.html).
| 1.READ VALUE USING MASS AIR FLOW METER (MAF) |
Connect the intelligent tester to the DLC3.
Start the engine.
Turn the tester on.
Enter the following menus: Powertrain / Engine / Data List / MAF.
Read the values displayed on the tester.
- Result:
Mass Air Flow Rate (gm/s)
| Proceed to
|
0.0
| A
|
271.0 or more
| B
|
Between 1.0 and 270.0 (*1)
| C
|
*1: The value must be changed when the throttle valve is open or closed.
| |
|
| | CHECK FOR INTERMITTENT PROBLEMS |
|
|
| 2.INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE) |
Disconnect the C2 mass air flow (MAF) meter connector.
Turn the ignition switch to the ON position.
Measure the voltage according to the value(s) in the table below.
- Standard voltage:
Tester Connection
| Specified Condition
|
+B (C2-3) - Body ground
| 9 to 14 V
|
Reconnect the MAF meter connector.
| 3.INSPECT MASS AIR FLOW METER (VG VOLTAGE) |
Inspect the output voltage.
Apply battery voltage across terminals +B and E2G.
Connect the positive (+) tester probe to terminal VG, and negative (-) tester probe to terminal E2G.
Measure the voltage between the terminals.
- Standard voltage:
Tester Connection
| Specified Condition
|
5 (VG) - 4 (E2G)
| 0.2 to 4.9 V
|
| 4.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) |
Disconnect the C2 MAF meter connector.
Disconnect the C58 (RHD) or C55 (LHD) ECM connector.
Measure the resistance between the terminals.
- Standard resistance (Check for open):
- RHD:
Tester Connection
| Specified Condition
|
VG (C58-72) - VG (C2-5)
| Below 1 Ω
|
E2G (C58-73) - E2G (C2-4)
| Below 1 Ω
|
- LHD:
Tester Connection
| Specified Condition
|
VG (C55-72) - VG (C2-5)
| Below 1 Ω
|
E2G (C55-73) - E2G (C2-4)
| Below 1 Ω
|
- Standard resistance (Check for short):
- RHD:
Tester Connection
| Specified Condition
|
VG (C58-72) or VG (C2-5) - Body ground
| 10 kΩ or higher
|
E2G (C58-73) or E2G (C2-4) - Body ground
| 10 kΩ or higher
|
- LHD:
Tester Connection
| Specified Condition
|
VG (C55-72) or VG (C2-5) - Body ground
| 10 kΩ or higher
|
E2G (C55-73) or E2G (C2-4) - Body ground
| 10 kΩ or higher
|
Reconnect the MAF meter connector.
Reconnect the ECM connector.
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 5.INSPECT FUSE (EFI NO. 3) |
Remove the EFI No. 3 fuse from the engine room R/B.
Measure the EFI No. 3 fuse resistance.
- Standard resistance:
- Below 1 Ω
Reinstall the EFI No. 3 fuse.
| 6.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ENGINE ROOM JUNCTION BLOCK) |
Disconnect the C2 MAF meter connector.
Remove the engine room junction block from the engine room R/B.
Measure the resistance between the terminals.
- Standard resistance:
- Check for open:
Tester Connection
| Specified Condition
|
+B (C2-3) - 1E-6 (Engine room R/B)
| Below 1 Ω
|
- Check for short:
Tester Connection
| Specified Condition
|
+B (C2-3) or 1E-6 (Engine room R/B) - Body ground
| 10 kΩ or higher
|
Reinstall the engine room junction block.
Reconnect the C2 MAF meter connector.
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 7.INSPECT ENGINE ROOM JUNCTION BLOCK (EFI RELAY) |
Remove the engine room junction block from the engine room R/B.
Inspect the EFI relay.
Measure the EFI relay resistance.
- Standard resistance:
Tester Connection
| Specified Condition
|
1E-12 - 1E-6
| 10 kΩ or higher
|
1E-12 - 1E-6
| Bellow 1 Ω
(Apply battery voltage between terminals 1E-9 and 1E-10)
|
Reinstall the engine room junction block.
| | REPLACE ENGINE ROOM JUNCTION BLOCK |
|
|
| OK |
|
|
|
| CHECK ECM POWER SOURCE CIRCUIT |
|
| 8.CHECK HARNESS AND CONNECTOR (SENSOR GROUND) |
Disconnect the C2 MAF meter connector.
Measure the resistance between the terminals.
- Standard resistance:
Tester Connection
| Specified Condition
|
E2G (C2-4) - Body ground
| Below 1 Ω
|
Reconnect the MAF meter connector.
| 9.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) |
Disconnect the C2 MAF meter connector.
Disconnect the C58 (RHD) or C55 (LHD) ECM connector.
Measure the resistance between the terminals.
- Standard resistance (Check for open):
- RHD:
Tester Connection
| Specified Condition
|
VG (C58-72) - VG (C2-5)
| Below 1 Ω
|
E2G (C58-73) - E2G (C2-4)
| Below 1 Ω
|
- LHD:
Tester Connection
| Specified Condition
|
VG (C55-72) - VG (C2-5)
| Below 1 Ω
|
E2G (C55-73) - E2G (C2-4)
| Below 1 Ω
|
- Standard resistance (Check for short):
- RHD:
Tester Connection
| Specified Condition
|
VG (C58-72) or VG (C2-5) - Body ground
| 10 kΩ or higher
|
E2G (C58-73) or E2G (C2-4) - Body ground
| 10 kΩ or higher
|
- LHD:
Tester Connection
| Specified Condition
|
VG (C55-72) or VG (C2-5) - Body ground
| 10 kΩ or higher
|
E2G (C55-73) or E2G (C2-4) - Body ground
| 10 kΩ or higher
|
Reconnect the MAF meter connector.
Reconnect the ECM connector.
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
