Crankshaft Position Variation Learn

Engine Controls and Fuel - 5.3L L84 or 6.2L L87 | Repair Instructions | Document ID: 4533949 Diagnostic Instructions Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis Description The crankshaft position sensor variation or reluctor ring learn is used to calculate reference period errors caused by slight tolerance variations in the crankshaft and the crankshaft position sensor. The calculated error allows the ECM to accurately compensate for reference period variations. This enhances the ability of the ECM to detect misfire events over a wider range of engine speed and load. The compensation values are stored in ECM memory after a learn procedure has been performed. When to Perform the Procedure

Note

Failure to perform this procedure may result in poor system performance, DTCs being set, or customer dissatisfaction. Perform this procedure when the following component has been serviced: B26 Crankshaft Position Sensor Any repair which disturbs the alignment between the components: B26 Crankshaft Position Sensor & Crankshaft Crankshaft Crankshaft Balancer Engine Assembly Conditions for Running the Procedure DTC P0117, P0118, P0335, P0336 = Not set ECT = Greater than 60°C (140°F) Ignition Voltage = Greater than 11 V Reference Information Scan Tool Reference Control Module References With Scan Tool

1. Ignition » On / Vehicle » In Service Mode
2. Verify there are no other DTCs set, except for DTC P0300−P0308, P0315. ⇒ If any other DTCs are set Refer to: Diagnostic Trouble Code (DTC) List - Vehicle ⇓ If no other DTCs are set
3. Select: Module Diagnostics
4. Select: Body Control Module
5. Select: Configuration/Reset Functions
6. Select: Brake Pedal Position Sensor Learn
7. Follow the instructions on the scan tool. Verify the scan tool parameter: Brake Pedal Position Sensor Learn = Yes ⇒ If not the specified state Repeat step 6 ⇓ If the specified state
8. Select: Module Diagnostics
9. Select: Engine Control Module
10. Select: Configuration/Reset Functions
11. Select: Learn Functions
12. Select: Crankshaft Position Variation Learn
13. Follow the instructions on the scan tool. Verify the scan tool procedure was successful. ⇒ If the procedure was not successful and first time here 13.1. Ignition/Vehicle » Off 13.2. Verify the following conditions do not exist: B26 Crankshaft Position Sensor & Reluctor Ring — Foreign material passing between the components / Incorrect air gap Battery Voltage — Low Crankshaft Bearing — Worn Crankshaft — Excessive runout / Visible Damage Reluctor Ring — Misaligned / Visible Damage Signal circuit @ B26 Crankshaft Position Sensor — Electromagnetic Interference ⇒ If a condition exists » Repair or replace as necessary ⇒ If no condition exists » Repeat step 8 ⇒ If the procedure was not successful and performed 4 times or less Repeat step 12 ⇒ If the procedure was not successful and performed 5 times Replace the component: K20 Engine Control Module ⇓ If the procedure was successful
14. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification For control module replacement, programming, and setup refer to: Control Module References