Tooth Error Correction (TEC) Service Bay Guidelines
Deceleration Fuel Cut-OffThis procedure is very convenient because it can be done in the service bay.
CAUTION: Appropriate safety measures should be taken to assure the safest conditions possible for all those people in the nearby vicinity of where the tooth error learn procedure is being performed.
Vehicle Preparation Requirements and Safety Issues
The vehicle needs sufficient engine oil, automatic transmission fluid, manual transmission gear box oil, power steering fluid, coolant, and brake fluid. Engine noise and exhaust should be considered by each assembly plant when deciding the location to perform the tooth error learn. Proper safety precautions should be taken. Anticipate unusual events such as a manual transmission accidentally being bumped into gear or a foot slipping off a clutch at high engine speed. The vehicle may cause other vehicles to be hit. If the transmission is in Park during the high engine speeds, the transmission Park Ratchet experiences excessive vibration and may momentarily slip. The vehicle is typically then in a Neutral type state and may roll, especially if the vehicle is on an incline. Under this condition the transmission should not slip into gear.
The following summarizes the engine preparation requirements for a tooth error learn.
Requirements:
1. At least 4 minutes of engine run time is required to have occurred at least once during the life of the vehicle to insure that all of the oil passages are flushed of debris from machining, casting, and assembly.
2. At least 5 seconds of engine run time is required during the same key cycle as the tooth error learn to fill the oil passages and provide proper lubrication. 10 seconds is the preferred guideline.
3. At least 65 degrees Celsius Coolant temperature. Engine oil temperature of 35 degrees Celsius is required for lubrication, which correlates (in most engines) to 65 degrees Celsius Coolant temperature. This is a recommendation to insure a sufficiently lubricated engine 65 degrees Celsius Coolant temperature correlates to an engine oil temperature of 38 degrees Celsius.
4. Vehicle must be in Park or Neutral. For a manual transmission vehicle, the clutch does not need to be depressed. The tooth error learn may be performed with either:
1. Gear box in Neutral, it does not matter if the clutch is depressed or not.
2. Gear Box in a gear and clutch depressed.
NOTE: The first option is the recommended option due to safety concerns. The second option has the risk of the operators foot slipping off of the clutch with the vehicle being revved up and in gear.
5. A/C should always be turned OFF before performing the TEC learn procedure.
6. A Class II command from the Tech 2 is required to invoke the TEC learn procedure.
7. No Camshaft and/or Crankshaft Sensor DTC Codes present.
Tooth Error Learn Procedures
The following steps are required to learn the tooth error once the above mentioned vehicle preparation requirements are met:
1. Make sure that the tooth error learn procedure has been invoked with the Tech 2, other wise when the throttle is depressed, the RPM would go to the high RPM fuel cutoff and not be cutoff at the lower tooth error learning fuel cutoff limit.
2. Depress the brake pedal for safety reasons.
3. Depress the throttle pedal to Wide Open Throttle (WOT) and keep the throttle at 100 % for the duration of the Tooth Error Correction (TEC) learning process until the TEC is learned or the number of attempts to learn has been exceeded. The RPM will be limited to the upper TEC RPM limit until one of the two above mentioned conditions are met and the throttle is released to less than 5 % Throttle Position Sensor (TPS). After this, the RPM limit will be the normal redline RPM limit.
The tooth error learning diagnostic will learn the tooth error as the engine decelerates in fuel cutoff.
During the tooth error learning procedure. TEC specific information is available which will indicate that the tooth error was properly learned and completed.
Considerations For Locating The Tooth Error Learning Procedure
The area that the tooth error learn is done should be well ventilated or have vehicle exhaust elimination system which attaches to the tail pipe and draws the vehicle exhaust out of the building.
CAUTION: Appropriate safety measures should be taken to assure the safest conditions possible for all those people in the nearby vicinity of where the tooth error learn procedure is being performed. If possible, anchored or secured safety barriers should be in place in at least the front of the vehicle and in the back of the vehicle if possible to reduce the possibility of accidents. The figure shows the proper placement of a frontal safety barrier.