DTC P0105: ABSOLUTE PRESSURE (AP) SENSOR Infiniti I30 I

1. Check Power Supply - Turn ignition off. Disconnect AP sensor harness connector. (Scheme 8) Turn ignition on. Measure voltage between sensor harness connector terminal No. 3 (Red wire) and ground. If about 5 volts are present, go to next step. If about 5 volts are not present, repair harness or connectors as necessary.
2. Check Ground Circuit - Turn ignition off. Loosen and retighten engine ground bolts. see scheme 6 Check for continuity between sensor connector terminal No. 1 (Black wire) and engine ground. If continuity is present, go to next step. If continuity is not present, repair Black wire circuit between absolute pressure sensor and ECM or A/T control unit.
3. Check Input Signal Circuit - Leave ignition off. Disconnect ECM harness connector. Check continuity between sensor connector terminal No. 2 (White wire) and ECM harness connector terminal No. 61. If continuity is present, go to next step. If continuity is not present, repair harness or connectors as necessary.
4. Check Component - Remove absolute pressure sensor. Leave connector connected. Turn ignition on. Measure voltage between sensor connector terminal No. 2 (White wire) and engine ground. (Scheme 9) Using vacuum pump, apply 31.5 in Hg. to sensor. Voltage should be about 4.6 volts. Apply 3.9 in Hg. to sensor. Voltage should be about 0.5 volts. If voltage drop is as specified, testing is complete. If voltage is not as specified, replace sensor and perform FINAL CHECK.

Scheme 8

Scheme 9