P1000

OBD SYSTEM READINESS function not yet complete

Detection Conditions

One or more of the following diagnostic trouble code detection conditions have not yet been satisfied.  Performing the appropriate DRIVE MODE condition will clear P1000 from ECU memory and establishing SYSTEM READINESS.  If, after performing all detection conditions, a fault is indicated, one or more of the following codes will be stored and appropriate OBD troubleshooting steps should be implemented.

• Oxygen sensor operation (P0130 / P0135 / P0150 / P0155)
• Fuel control (P0125 / P0170 / P0173)
• Misfire detection (P0300 / P0301 / P0302 / P0303 / P0304 / P0305 / P0306)
• EGR system operation (P0400)
• Catalyst efficiency (P0420 / P0421 / P0430 / P0431)
• Evaporative emissions system operation (P0440)

DRIVE MODE Conditions

DRIVE MODE 1 - Fuel trim memory initialization

DRIVE MODE 2 - EGR system repair verification

DRIVE MODE 3 - Oxygen sensor and catalyst repair verification

DRIVE MODE 4 - Evaporative emissions system repair verification

OBD-II Compliance & 1995 Models

Early implementations (before 1996) of OBD-II utilize a non-standard method of determining SYSTEM READINESS using DTC P1000.  Such vehicles are considered "OBD-I compliant" for emissions testing but are essentially OBD-II for troubleshooting purposes.

Persistent P1000

If no fault is indicated other than P1000 after several drive cycles, check for a blown ROOM fuse or faulty battery connections.

[P1000 - 1995 Mazda Millenia factory service manual]