DTC P0450: EVAP CONTROL SYSTEM PRESSURE SENSOR Infiniti I30 I

1. Check Power Supply - Turn ignition off. Disconnect EVAP control system pressure sensor harness connector. (Scheme 31) Turn ignition on. Using a voltmeter, measure voltage between EVAP control system pressure sensor harness connector terminal No. 3 (Red wire) and ground. If measured voltage is about 5 volts, go to next step. If voltage is not about 5 volts, check for faulty joint connector No. 1 or fault in Red wire. Repair or replace as required.
2. Check Ground Circuit - Turn ignition off. Loosen and retighten engine ground bolts. see scheme 6 Using an ohmmeter, check continuity between EVAP control system pressure sensor harness connector terminal No. 1 (Black wire) and engine ground. If no continuity exists, repair open in Black wire. If continuity exists, go to next step.
3. Check Input Signal Circuit - Leave ignition off. Disconnect ECM harness connector. Using an ohmmeter, check continuity between EVAP control system pressure sensor harness connector terminal No. 2 (White wire) and ECM connector terminal No. 62. If no continuity exists, repair open in White wire. If continuity exists, go to next step.
4. Check EVAP Canister Vent Control Valve - Go to step 4) of DTC P0440: EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM. Repair or replace if necessary. If EVAP canister vent control valve is okay, go to next step.
5. Remove EVAP control system pressure sensor. Reconnect harness connector. Connect vacuum pump to vacuum port. Measure voltage between ground and EVAP control system pressure sensor harness connector terminal No. 2 (White wire). (Scheme 32) Voltage should be about 4.6 volts. Apply 2.8 in Hg to sensor. Voltage should be about 0.5 volt. If voltage is not as specified, replace EVAP control system pressure sensor. If voltage is as specified, disconnect system harness connectors and inspect for damage or corrosion. Repair as necessary and retest.

Scheme 31

Scheme 32