| Circuit Diagram |

Signal Waveform Idle rail pressure regulator waveform
Inspection 1. Turn the ignition switch OFF and disconnect the battery negative (-) cable. 2. Disconnect the fuel pressure regulator valve connector.
C
Inspection 1. Turn the ignition switch ON. 2. Connect the GDS. 3. Emit intensive light toward the photo sensor using a lamp, and check the output voltage change. 4. The voltage will rise with higher intensive light and fall with lower intensive light.