LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 1997 >> Century Custom >> Repair and Diagnosis >> Body & Frame >> Body, Cab Control Systems >> Body Control Module >> Diagnosis & Repair >> DTC U1255, Loss Of Class 2 Serial Data Fault (General) >> Testing

DTC U1255, Loss Of Class 2 Serial Data Fault (General): Testing

  1. If BCM diagnostic system check was performed, go to next step. If BCM diagnostic system check was not performed, go to BCM DIAGNOSTIC SYSTEM CHECK  .
  2. Turn ignition off. Connect scan tool. Turn ignition on. Using scan tool, attempt to establish communication with PCM. If scan tool communicates with PCM, go to next step. If scan tool does not communicate with PCM, go to appropriate TESTS W/CODES article in ENGINE PERFORMANCE section. Refer to menu below.
  3. Check class 2 serial data link for intermittent open, short to ground, short to voltage, or poor connections at BCM, PCM or splice pack SP205. If problem is found, repair as necessary and go to step 6). If no problem is found, go to next step.
  4. Turn ignition off. Reinstall all components and connectors. Clear DTCs. Check for DTCs. If DTC U1255 sets again, go to next step. If DTC U1255 does not set again, system is operating properly.
  5. Turn ignition off. Replace BCM. See REMOVAL & INSTALLATION  . Reprogram BCM. See BCM PROGRAMMING. Go to next step.
  6. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Using scan tool, clear DTCs. Perform BCM DIAGNOSTIC SYSTEM CHECK  .
scientia non olet · About LEMON Manuals