FixVault
Home › Jeep › 1992 › Cherokee Limited › Repair and Diagnosis › Engine Performance › System › Engine Controls - Tests W/Codes › No-Fault Tests › Test NF-8A - Checking Park/Neutral Switch Input (A/T Only)

Test NF-8A - Checking Park/Neutral Switch Input (A/T Only)

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION  . For wiring diagram, see WIRING DIAGRAMS  at end of article.
  1. Using DRB-II, read park/neutral switch input state. While observing DRB-II display, move gear selector in and out of Park and Reverse positions. If display shows P/N and D/R, system is functioning properly. If display does not show P/N and D/R (Wrangler with AW-4 automatic transmission), service or replace park/neutral switch. If display does not show P/N and D/R (all other applications), go to next step.
  2. Turn ignition off. Place gear selector in Park position. Disconnect engine controller connector. Disconnect battery quick disconnect cable (at battery). Place DRB-II in ohmmeter mode. Probe Black/Tan wire (Black/White wire on Wrangler) at engine controller connector terminal No. 30. While observing DRB-II display, move gear selector in and out of Park and Reverse positions.
  3. If display switches from less than 5 ohms to more than 5 ohms, replace engine controller. Perform VERIFICATION TEST VER-2  . If display always stays less than 5 ohms, repair short to ground in Black/Tan wire (Black/White wire on Wrangler). Perform VERIFICATION TEST VER-2  . If display does not always stay less than 5 ohms, go to next step.
  4. Disconnect park/neutral switch connector. Using a DVOM, check resistance of Black/Tan wire (Black/White wire on Wrangler) between park/neutral switch connector and engine controller connector terminal No. 30. If resistance is less than 10 ohms, replace park/neutral switch. Perform VERIFICATION TEST VER-2  . If resistance is 10 ohms or more, repair open Black/Tan wire (Black/White wire on Wrangler). Perform VERIFICATION TEST VER-2  .
About FixVault