P1000: OBD System Readiness Test Not Complete (Ford, Mazda, Jaguar)
Quick Answer
Safe to drive (short-term)
P1000 means the car's built-in emissions self-tests (the readiness monitors) have not all finished since the engine computer's memory was last cleared. It is a manufacturer-specific code: Ford (including Lincoln and Mercury), Mazda and Jaguar use it this way, Land Rover lists it as engine control module memory erased with no codes stored, and other makes may define it differently. It most often shows up after a battery disconnection, a computer reset or cleared codes, and it normally goes away on its own once the car has completed a full drive cycle.
- Severity
- Low · Emissions
Up to €400, depending on your car.
A scan shows whether P1000 is really stored on your car, which codes sit next to it and how urgent each one is.
A scan needs a Bluetooth OBD2 adapter (Bluetooth LE on iPhone), about €25-60; the built-in demo runs without one. See which adapter to buy
What does P1000 mean?
P1000 is a emissions-related diagnostic trouble code classified as low severity.
What are the symptoms of P1000?
- No change in how the car drives
- P1000 stored, often with no check engine light
- Readiness monitors shown as not ready on a scan tool
- Appears right after a battery change, disconnection or code clearing
- A failed or refused emissions or roadworthiness check because monitors are not ready
- Code that keeps returning after several weeks of normal driving
What causes P1000?
Battery disconnected or replaced, which wipes the computer's memory
: high
Fault codes cleared with a scan tool before the monitors had time to run again
: high
Powertrain control module (PCM) disconnected, reset or reprogrammed
: medium
New car or recent repair, with the drive cycle not yet completed
: medium
A real fault that stops one monitor from finishing, such as an oxygen sensor, EVAP leak or thermostat problem
: medium
Fuel cap loose or missing, which can keep the EVAP self-test from completing
: low
On Ford vehicles with a power take-off (PTO) circuit, a PTO circuit shorted to battery voltage or switched on during testing
: low
Is it safe to drive with P1000?
Generally yes, for short-term driving. The car drives normally. P1000 is a status message, not a failed part: the emissions self-tests have not all finished since the computer's memory was last reset. Keep driving in a normal mix of conditions. Only worry if other codes are stored with it or the warning light is on, because a real fault can stop a self-test from ever finishing.
How do you diagnose P1000?
- Read all stored codes. If P1000 is the only one, treat it as a status message. If other codes are stored, fix those first, because a real fault can keep a monitor from finishing
- Ask what happened recently: battery change or disconnection, codes cleared, computer reset or work on the engine. Any of these explains the code
- Use a reader that shows readiness status (standard OBD2 Mode 01) to see which monitors are not ready. A generic reader can show this; it cannot run the tests for you
- Drive normally, with a mix of a cold start, steady-speed driving, stop-and-go and slowing down. One short trip is rarely enough. Drive cycles differ by maker, so check the owner's manual or ask a dealer for yours
- Check that the fuel cap is fitted and clicked tight, since an EVAP self-test that cannot finish keeps the status open
- Re-read the readiness status after several mixed trips. If the same monitor stays not ready, look for a hidden fault in the system that monitor tests
- Before an inspection, confirm every required monitor shows ready. Clearing codes again resets them to not ready
- After any repair, a workshop should run a final scan to confirm P1000 and the monitors have cleared properly
How much does P1000 cost to fix?
| Repair | Parts Cost | Labor Cost | Total Estimate | DIY Difficulty |
|---|---|---|---|---|
| Complete the drive cycle yourself (normal mixed driving) | €0–€0 | €0–€0 | €0–€0 | Easy |
| Workshop read-out of readiness status and stored codes | €0–€0 | €30–€80 | €30–€80 | Professional |
| Replace a weak battery that keeps losing memory | €60–€200 | €0–€50 | €60–€250 | Easy |
| Replace or re-seat the fuel cap | €10–€50 | €0–€0 | €10–€50 | Easy |
| Replace an oxygen sensor that blocks its monitor | €30–€150 | €50–€250 | €80–€400 | Moderate |
Prices estimated as of October 2026. Costs vary by region, vehicle, and shop.
P1000 on specific vehicles
P1000 on Ford
Ford Bronco (1996)
P1000 on Jaguar
Jaguar S-Type (V6 and V8)
Related diagnostic codes
Common questions about P1000
- What does P1000 mean?
- P1000 is a manufacturer-specific code. On Ford, Mazda and Jaguar it means the OBD-II readiness monitors have not finished their self-tests. Land Rover lists it as engine computer memory erased, with no codes stored. In both cases it is a status message, not a failed part.
- Will P1000 clear by itself?
- Usually yes. The monitors run during normal driving, and the code goes away once they have all completed. It often takes several trips of mixed driving rather than one short drive. Drive cycles differ by maker, so the owner's manual or a dealer can give the exact conditions for your car.
- Does P1000 turn the check engine light on?
- On its own it usually does not, which is why a scan is the only reliable way to see it. If the light is on, look for other stored codes, because those are the real reason for the light.
- Why is P1000 still there after weeks of driving?
- A fault elsewhere may be stopping one monitor from completing, so the status never closes. Check which monitor is stuck at not ready and look for a related fault, such as an oxygen sensor, an EVAP leak or a thermostat that never reaches temperature.
- Can I pass an inspection with P1000 stored?
- It depends on the country and the test. A station that reads the OBD system can see monitors flagged as not ready and may ask you to come back after more driving. Check the readiness status first and drive the car through a full drive cycle before booking.
- Do I need a mechanic for P1000?
- Not if it appeared right after a battery change or code clearing and no other codes are stored. Drive normally and re-check. See a workshop if other codes are present or P1000 will not clear after repeated mixed trips.
Read our detailed guides
Sources
- broncozone.com broncozone.com/goto/post?id=141995
- vehicleservicepros.com vehicleservicepros.com/training-and-resources/tech-tips/article/21077195/ask-the
- kbb.com kbb.com/obd-ii/p1000
- host.jcna.com host.jcna.com/sites/default/files/STYPE.pdf