Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Aids
Perform this test when instructed during QUICK TEST or if directed by other test procedures. This code indicates that On Board Diagnostics II (OBD II) system self-testing has not been completed. To erase DTC P1000, a complete drive cycle, with successful OBD II system self-test, must occur.
A drive cycle consists of vehicle warmed to normal engine temperature and operated in all speed ranges. After self-test successfully completes, SYSTEM PASS can be obtained from PCM.
DTC P1000 will set in PCM memory when any of the following conditions occur:
- Battery or PCM has been disconnected.
- An OBD II monitor has failed before completion of drive cycle.
- PCM memory has been erased with a scan tester.
- Step 1) Check For Other DTCs If any trouble codes are present, service as necessary. If no trouble codes are present, and vehicle is equipped with PTO, go to next step. If no trouble codes are present, and vehicle is not equipped with PTO, go to step 4).
- Step 2) Power Take Off (PTO) Applications If vehicle is equipped with PTO, go to next step. If vehicle is not equipped with PTO, replace PCM and repeat QUICK TEST .
- Step 3) Check PTO PID Turn ignition off. Connect scan tester to Data Link Connector (DLC). Start engine and allow to idle. Using scan tester, access PTO STAT PID. Cycle PTO switch/activator on and off. If PTO STAT PID does not cycle as specified, go to CIRCUIT TEST FB. If PTO STAT PID cycles on, pauses, and then cycles off, PTO is okay. Go to next step.
- Step 4) Attempt To Remove DTC P1000 Test drive vehicle to complete drive cycle. Cruise at 20-45 MPH for at least 4 minutes. Cruise at 30-40 MPH for at least 60 seconds. Cruise at 40-65 MPH for at least 80 seconds. If DTC P1000 is still present, go to next step. If DTC P1000 is not present, testing is complete.
- Step 5) Check VSS PID Turn ignition off. Connect scan tester to Data Link Connector (DLC). Using scan tester, access VSS PID. Test drive vehicle to complete drive cycle. If VSS PID is more than zero, go to next step. If VSS PID is zero, repair open in VSS circuit and repeat QUICK TEST .
- Step 6) Check ECT Temperature Ensure engine is at operating temperature. Using scan tester, access ECT PID. If ECT PID is more than 180°F (82°C), repeat drive cycle. If ECT PID is less than 180°F (82°C), repair cooling system fault and repeat QUICK TEST .
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.