df3: VREF Isolation
| Steps | _MAP/BP tester connected
_Key On _Disconnect MAP/BP |
| Result | (Only) Green light, VREF is OK. Replace MAP/BP sensor. Rerun Quick Test
"Less than 4V" light (Red) or no lights, VREF is too low. Remove MAP/BP tester. GO to PinPoint Test Step Continue "Greater than 6V" light (Red), VREF is too high. |
| Component | Barometric Absolute Pressure Sensor |
| Description | The
BP sensor measures barometric pressure using a frequency. This gives
the EEC information on engine load. The BP is used as a barometric
pressure sensor for altitude compensation, updating the EEC during Key
On Engine Off and every wide-open throttle.
The EEC uses the BP information for: Spark advance EGR flow Air/Fuel ratio |
| Location | Mounted behind Integrated Relay Controller; in front of passenger strut tower. |
| Wire Colors | Orange with White stripe
Light Green with Black stripe Black with White stripe |
| Notes | While the BP has a port typical of a MAP sensor, this port is NOT hooked to any vacuum source, and simply is a atmosphere vent. |