FixVault
Home › GMC › 1998 › Yukon 4WD › Repair and Diagnosis › Accessories & Equipment › Communication Devices › Data Link Communications System › System Tests › Scan Tool Does Not Communicate With Class 2 Data Line

Scan Tool Does Not Communicate With Class 2 Data Line

  1. Perform DIAGNOSTIC SYSTEM CHECK .
  2. Disconnect scan tool from DLC. Turn ignition to RUN. Check voltage with DVOM between DLC terminal Nos. 2 and 4. If voltage is greater than 7 volts, go to next step. If voltage is not greater than 7 volts, go to step  10.
  3. Turn ignition OFF. Disconnect C100. Check voltage with DVOM between DLC terminal Nos. 2 and 4. If voltage is not greater than 7 volts, go to next step. If voltage is greater than 7 volts, go to step  6.
  4. Turn ignition OFF. Connect C100. Disconnect EBCM connector C1. Check voltage with DVOM between DLC terminal Nos. 2 and 4. If voltage is greater than 7 volts, go to next step. If voltage is not greater than 7 volts, go to step  18.
  5. Turn ignition OFF. Disconnect PCM/VCM. Check voltage with DVOM between DLC terminal Nos. 2 and 4. If voltage is greater than 7 volts, go to step  8. If voltage is not greater than 7 volts, go to step  18.
  6. Turn ignition OFF. Disconnect EVO/Passlock™ module. Check voltage with DVOM between DLC terminal Nos. 2 and 4. If voltage is greater than 7 volts, go to next step. If voltage is not greater than 7 volts, go to step  18.
  7. Turn ignition OFF. Disconnect transfer case shift control module connector C1. Check voltage with DVOM between DLC terminal Nos. 2 and 4. If voltage is greater than 7 volts, go to step  9. If voltage is not greater than 7 volts, go to step  18.
  8. Repair short to voltage in Purple 1807 circuit wiring between C100 and EBCM and PCM/VCM. Perform DIAGNOSTIC SYSTEM CHECK .
  9. Repair short to voltage in Purple 1807 circuit wiring between DLC and EVO/Passlock™ module, C100 and transfer case shift control module. Connect C100. Perform DIAGNOSTIC SYSTEM CHECK .
  10. Turn the ignition OFF. Check for continuity with DVOM between ground and DLC terminal No. 2. If there is continuity, go to next step. If there is not continuity, perform DIAGNOSTIC SYSTEM CHECK .
  11. Disconnect C100. Check for continuity with DVOM between ground and DLC terminal No. 2. If there is not continuity, go to next step. If there is continuity, go to step  14.
  12. Reconnect C100. Disconnect EBCM connector C1. Check for continuity with DVOM between ground and DLC terminal No. 2. If there is continuity, go to next step. If there is not continuity, go to step  18.
  13. Disconnect the PCM/VCM. Check for continuity with DVOM between ground and DLC terminal No. 2. If there is continuity, go to step  16. If there is not continuity, go to step  18.
  14. Disconnect EVO/Passlock™ module. Check for continuity with DVOM between ground and DLC terminal No. 2. If there is continuity, go to next step. If there is not continuity, go to step  18.
  15. Disconnect transfer case shift control module connector C1. Check for continuity with DVOM between ground and DLC terminal No. 2. If there is continuity, go to step  17. If there is not continuity, go to step  18.
  16. Repair short to ground in Purple 1807 wiring between C100 and EBCM and PCM/VCM. Perform DIAGNOSTIC SYSTEM CHECK .
  17. Repair short to ground in Purple 1807 wiring between DLC and EVO/Passlock™ module, C100 and transfer case shift control module. Connect C100. Perform DIAGNOSTIC SYSTEM CHECK .
  18. Replace module most recently disconnected. Perform DIAGNOSTIC SYSTEM CHECK .
About FixVault