DTC P1259: VTEC System Malfunction Special Tools Required Oil pressure gauge attachment 07NAJ-P070100 Low pressure gauge 07406-0070001 Hose oil pressure 07ZAJ-S5A0200 Reset the ECM (see page 11-3). Check the engine oil level, and refill if necessary. Start the engine. Hold the engine at 3.000 rpm (min-1) with no load (in Park or neutral) unit the radiator fan comes on. Road test the vehicle: Accelerate in 1st gear to an engine speed over 4,000 rpm. Hold that engine speed for at least 2 seconds. If DTC P1259 is not repeated during the first road test, repeat this test 2 more times. Is DTC P1259 indicated? YES - Go to step 5. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the VTEC solenoid valve and at the ECM. Turn the ignition switch OFF.

Disconnect the VTEC oil pressure switch 2P connector. Check for continuity on the VTEC oil pressure switch between the VTEC oil pressure switch 2P connector terminals No. 1 and No. 2. VTEC OIL PRESSURE SWITCH 2P CONNECTOR Terminal side of male terminals Is there continuity? YES - Go to step 8. NO - Replace the VTEC oil pressure switch. Turn the ignition switch ON (II). Measure voltage between the VTEC oil pressure switch 2P connector terminal No. 1 and body ground. VTEC OIL PRESSURE SWITCH HARNESS 2P CONNECTOR Wire side of female terminals Is there battery voltage? YES - Go to step 14. NO - Go to step 10. aaa