DTC P0102: Mass or Volume Air Flow Circuit Low Input; DTC P0103: Mass or Volume Air Flow Circuit High Input: Procedure
WARNING: This page is about a different car, the 2013 Lexus IS 350C. However, it is still accessible from the selected car via links, so may be relevant.
- READ DTC OUTPUT
- Connect the Techstream to the DLC3.
- Turn the engine switch on (IG).
- Turn the Techstream on.
- Enter the following menus: Powertrain / Engine / Trouble Codes.
- Read the DTCs.
Result
Result Proceed to DTC P0102 is output A DTC P0103 is output B
B → See step 5
A: Go to next step
- CHECK HARNESS AND CONNECTOR (POWER SOURCE VOLTAGE)
- Disconnect the mass air flow meter connector.
- Turn the engine switch on (IG).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition E29-3 (+B) - Body ground Engine switch on (IG) 11 to 14 V TEXT IN ILLUSTRATION*a Front view of wire harness connector
(to Mass Air Flow Meter) - Reconnect the mass air flow meter connector.
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - EFI MAIN RELAY)
OK: Go to next step
- Disconnect the mass air flow meter connector.
- CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
- Disconnect the mass air flow meter connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open)
Tester Connection Condition Specified Condition E29-5 (VG) - E5-27 (VG) Always Below 1 Ω E29-4 (E2G) - E5-26 (E2G) Always Below 1 Ω Standard Resistance (Check for Short)
Tester Connection Condition Specified Condition E29-5 (VG) or E5-27 (VG) - Body ground Always 10 kΩ or higher - Reconnect the mass air flow meter connector.
- Reconnect the ECM connector.
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)
OK: Go to next step
- INSPECT MASS AIR FLOW METER
- Perform On-vehicle Inspection. Refer to ON-VEHICLE INSPECTION [08/2012 - ] .
- Perform Inspection. Refer to INSPECTION [08/2012 - ] .
- Inspect the function of the mass air flow meter.
- Connect the Techstream to the DLC3.
- Turn the engine switch on (IG).
- Turn the Techstream on.
- Enter the following menus: Powertrain / Engine / Data List / MAF.
- Start the engine.
- Check that the reading of the MAF value changes when the engine is raced.
OK
The reading changes.
NG → See step 7
OK → See step 8
- CHECK HARNESS AND CONNECTOR (SENSOR GROUND)
- Disconnect the mass air flow meter connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open)
Tester Connection Condition Specified Condition E29-4 (E2G) - Body ground Always Below 1 Ω - Reconnect the mass air flow meter connector.
NG → See step 6
OK → See step 7
- CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)
- Disconnect the mass air flow meter connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open)
Tester Connection Condition Specified Condition E29-4 (E2G) - E5-26 (E2G) Always Below 1 Ω - Reconnect the mass air flow meter connector.
- Reconnect the ECM connector.
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)
OK → See step 8
- REPLACE MASS AIR FLOW METER. Refer to REMOVAL [08/2012 - ]
- REPLACE ECM. Refer to REMOVAL [08/2012 - ]