Diagnostic Aids
WARNING: This page is about a different variant/trim than selected.
SIG RTN is a dedicated ground used by most EEC-V system sensors. VREF is a 5-volt reference voltage that is continuously output by PCM. This consistent voltage signal is used on all 3-wire sensors. This system test is only intended to diagnose the following components and circuits:
- A/C Pressure (ACP) Sensor, Barometric (BARO) Pressure Sensor, Differential Pressure Feedback EGR (DPFE) Sensor, Fuel Rail Pressure (FRP) Sensor, Fuel Tank Pressure (FTP) Sensor, Power Steering Pressure (PSP) Sensor & Throttle Position (TP) Sensor
- Vehicle Wiring Harness Circuits (SIG RTN & VREF)
- Powertrain Control Module (PCM)