Home ReviewsRefund
Home/Chrysler/LHS/Chrysler LHS II (1998-2001)/Repair manual/Testing & Diagnostics/DTC P1398-A: MISFIRE ADAPTIVE NUMERATOR AT LIMIT
Contents Wiring diagrams Section: Testing & Diagnostics All sections

DTC P1398-A: MISFIRE ADAPTIVE NUMERATOR AT LIMIT Chrysler LHS II

Testing & Diagnostics ~339 words

Note. For connector terminal ID, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.

  1. Using scan tool, read DTCs. If GLOBAL GOOD TRIP displayed is equal to zero, go to next step. If GLOBAL GOOD TRIP displayed is not equal to zero, go to step 4 .
  2. Turn ignition off. Disconnect connector at Crankshaft Position (CKP) sensor. Inspect CKP sensor connector for pushed out terminals or damage. Repair CKP sensor connector as necessary. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S06971814902000030800000) . If CKP sensor is okay, go to next step.
  3. Remove CKP sensor. Inspect slots in flexplate for damage or foreign material. If damage or foreign material is present, repair as necessary. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S06971814902000030800000) . If damage or foreign material is not present, replace CKP sensor. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S06971814902000030800000) .
  4. Condition to set trouble code is not present at this time. MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT DTC sets if one of the Crankshaft Position (CKP) sensor target windows has more than 2.86 percent variance from the reference window. Possible causes are: CKP sensor improperly installed, CKP sensor failure, CKP flexplate target variation, severely worn crankshaft bearings, faulty wiring connection, Powertrain Control Module (PCM) failure or low compression in one or more cylinders. Go to next step.
  5. Visually inspect CKP sensor and connector. If any problems are present, repair as necessary. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S06971814902000030800000) . If no problems are present, go to next step.
  6. Using scan tool in Miscellaneous Menu, clear PCM (battery disconnect). Using scan tool, access MIS-FIRE PRE-TEST screen. Road test vehicle and relearn adaptive numerator. Adaptive numerator relearn can be done by driving vehicle to 5000 RPM in low gear and snapping throttle quickly closed 3 times. If adaptive numerator relearned, test is complete. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S06971814902000030800000) . If adaptive numerator did not relearn, return to step 1 and repeat procedure.

More articles — Engine Controls - Tests W/codes