Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Mode 1 Procedure

Mode 1, 2, 3:





1. Ensure that there are no vacuum and/or air system intake leaks.
2. Run the engine for 3 minutes or until the engine reaches operating temperature 80°C (176°F).
3. Ensure that all accessories are OFF, including A/C.
4. Ground the TEN pin in the data link connector.
5. Ensure proper ignition timing and correct if needed.
6. Key OFF.
7. Set the parking brake and block the drive wheels.
8. Place the transmission in PARK (A/T) or NEUTRAL (M/T).
9. Restart the engine.
10. Increase the engine speed to 1750 +/- 125 rpm and hold it there for 15 seconds.
11. Repeat step 10 for each of the following engine speeds: 2000 +/- 125 rpm, 2250 +/- 125 rpm, 3000 +/- 250 rpm, 3500 +/- 250 rpm, 4000 +/- 250 rpm, 4250 +/- 125 rpm, 4500 +/- 125 rpm, 4750 +/- 250 rpm, 5000 +/- 125 rpm, 5250 +/- 125 rpm, and 5500 +/- 125 rpm.

NOTE: If the cooling fan engages during the idle portion of this test, continue idling for 30 seconds after the cooling fan disengages.

12. Release the throttle and let engine idle for approximately 30 seconds.
13. If an active MODE 1 Parameter Identification (PID) is available, monitor the PID to verify successful Mode 1 completion. If Mode 1 cannot be completed despite accurately following the procedure, go to Pinpoint Test QC to diagnose the cause of the Mode 1 failure. QC - OBD II Monitor Testing Not Complete (DTC P1000)
14. Key OFF.