LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chrysler >> 1994 >> LHS >> Repair and Diagnosis >> Body & Frame >> Body, Cab Control Systems >> Body Control Computer >> Testing >> Vehicle Communications Tests >> Test 139A - No Bus Bias
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test 139A - No Bus Bias

  1. If ignition was off during BUS test, turn ignition on, engine off. If ignition was on during BUS test, turn ignition off. Disconnect scan tool. Turn ignition on. Using an external voltmeter, check voltage between chassis ground and Data Link Connector (DLC) connector terminal No. 3 (Violet/Brown wire). If voltage is not 2.3-2.6 volts, go to step 3).
  2. If voltage is 2.3-2.6 volts, check voltage between chassis ground and DLC connector terminal No. 11 (White/Black wire). If voltage is not 2.3-2.6 volts, go to next step. If voltage is 2.3-2.6 volts, replace scan tool cable or cartridge as necessary.
  3. Turn ignition off. Disconnect Body Control Module (BCM). BCM is located behind right kick panel. Using an external ohmmeter, check resistance between BCM Bone connector terminals No. 7 and No. 8. If resistance is not 100-140 ohms, replace BCM. If resistance is 100-140 ohms, go to next step.
  4. Turn ignition on. Connect jumper wire between BCM Bone connector, terminal No. 8 (Violet/Brown wire) and ground. Using scan tool, select BODY, BODY COMPUTER, then SYSTEM TEST. Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open Violet/Brown wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  5. Move jumper wire to BCM Bone connector, terminal No. 7 (White/Black wire). Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open White/Black wire. If scan tool displays BUS SHORT TO GROUND, remove jumper wire and go to next step.
  6. Using external voltmeter, measure voltage on BCM Bone connector, terminal No. 19 (Pink wire). If voltage is 10 volts or less, repair Pink wire as necessary. If voltage is more than 10 volts, go to next step.
  7. Turn ignition on. Measure voltage on BCM Bone connector, terminal No. 13 (Dark Blue/White wire). If voltage is 10 volts or less, repair open Dark Blue/White wire. If voltage is more than 10 volts, go to next step.
  8. Turn ignition off. Using external ohmmeter, measure resistance of BCM Bone connector, terminal No. 14 (Black/Light Green wire). If resistance is 5 ohms or more, repair open to ground in Black/Light Green wire. If resistance is less than 5 ohms, replace BCM.
NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION  . For wiring schematics, see WIRING DIAGRAMS  in this article. Perform TEST VER-1 - VERIFICATION PROCEDURE  after each repair.
CAUTION: Always turn ignition off prior to disconnecting any module connector.
scientia non olet · About LEMON Manuals