Diagnosis & Repair
WARNING: This page is about a different car, the 2003 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.
- Turn ignition off. Airflow meter is bolted to top side of air intake hose, near upper cap on air cleaner assembly. If you do not have hand-held tester, go to step 2. Connect hand-held tester to DLC3. Turn ignition switch on. Blow air into MAF meter and check that air flow value of CURRENT DATA changes. See Fig 1. If value does not change, check wiring and ECM. Go to step 3.
- Turn ignition switch on. Connect positive tester probe of voltmeter to terminal VG of ECM and negative tester probe to terminal E2G. See Fig 2. Blow air into air flow meter and check if voltage fluctuates. If value does not change, check wiring and ECM. Go to step 3.
- Apply battery voltage across terminals No. 3 (+B) and 4 (E2G). Connect positive tester probe to terminal No. 5 (VG) and negative to terminal No. 4 (E2G). Blow air into MAF meter and check if voltage fluctuates. See Fig 3. If voltage does not fluctuate, repair or replace as necessary.
- Using an ohmmeter, measure resistance between terminals 2 (THA) and 1 (E2). See AIRFLOW METER RESISTANCE . If resistance is not as specified, repair or replace as necessary.
AIRFLOW METER RESISTANCE
| Temperature °F (°C) | Ohms |
|---|---|
| -4 (-20) | 12,500-16,900 |
| 68 (20) | 2190-2670 |
| 140 (60) | 500-680 |