Troubleshooting
DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUTCIRCUIT DESCRIPTION
DTC Detecting Condition:
The mass air flow meter uses a platinum hot wire. The hot wire mass air flow meter consists of a platinum hot wire, temperature sensor and a control circuit installed in a plastic housing. The hot wire mass air flow meter works on the principle that the hot wire and intake air temperature sensor located in the intake air bypass of the housing detect any changes in the intake air temperature.
The hot wire is maintained at the set temperature by controlling the current flow through the hot wire. This current flow is then measured as the output voltage of the mass air flow meter.
The circuit is constructed so that the platinum hot wire and temperature sensor provide a bridge circuit, with the power transistor controlled so that the potential of A and B remains equal to maintain the set temperature.
HINT: After confirming DTC P0100, P0102 or P0103, use the hand-held tester to check the mass air flow ratio from the "DIAGNOSIS/ENHANCED OBD II/DATA LIST/ALL DATA/MAF".
Wiring Diagram:
Step 4 - 8:
Step 2 - 3:
Step 4 - 5:
Step 6:
Step 7:
INSPECTION PROCEDURE
HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.
CHECK FOR INTERMITTENT PROBLEMS
hand-held tester only:
By putting the vehicle's ECM in the check mode, 1 trip detection logic is possible instead of 2 trip detection logic and sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.
1. Clear the DTC.
2. Set the check mode.
3. Perform a simulation test.
4. Check the connector and terminal.
5. Handle the connector.