LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 1999 >> Yukon Base, 4WD >> Repair and Diagnosis >> Accessories & Equipment >> Communication Devices >> Data Link Communications System >> System Tests >> Scan Tool Does Not Communicate With VCM

Scan Tool Does Not Communicate With VCM

  1. Perform DIAGNOSTIC SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition RUN. If MIL lights, go to next step. If MIL does not light, perform powertrain OBD system test. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS INTRODUCTION - GASOLINE - EXCEPT METRO, PRIZM & TRACKER article in ENGINE PERFORMANCE.
  3. Select "powertrain diagnostics" on scan tool main menu. If scan tool indicates "no data communication with vehicle" go to next step. If scan tool does not indicate "no data communication with vehicle" perform DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  4. Select "chassis diagnostics" on scan tool main menu. If scan tool can communicate with EBCM, go to next step. If scan tool cannot communicate with EBCM, perform DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  5. Turn ignition OFF. Disconnect connector C4 from VCM. Check for continuity with DVOM between VCM connector terminal No. 11 and S150. If there is no continuity, go to next step. If there is continuity, go to step  7.
  6. Repair open or resistance in Purple 1807 circuit wiring between VCM connector terminal 11 and S150. Perform DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  7. Replace VCM. See REMOVAL, OVERHAUL & INSTALLATION - TRUCKS article in ENGINE PERFORMANCE article. Perform DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
scientia non olet · About LEMON Manuals