PGM-FI System

DTC Troubleshooting (cont'd)

11-394  

DTC P1259: VTEC System Malfunction

Special Tools Required

  • Oil pressure gauge attachment 07NAJ-P070100
  • Low pressure gauge 07406-0070001
  • Hose oil pressure 07ZAJ-S5A0200
  1. Reset the ECM/PCM (see page 11-312).
  2. Check the engine oil level, and refill if necessary.
  3. Start the engine. Hold the engine at 3.000 rpm (min-1) with no load (in Park or neutral) until the radiator fan comes on.
  4. Road test the vehicle:

Accelerate in 1st gear to an engine speed over 4,000 rpm (min-1). 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/PCM.


  1. Turn the ignition switch OFF.
  2. Remove the resonator (see page 11-448).

  1. Disconnect the VTEC oil pressure switch 2P connector.
  1. 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 9.

NO

- Replace the VTEC oil pressure switch.


  1. Turn the ignition switch ON (II).
  2. 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 15.

NO

- Go to step 11.