LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Pontiac >> 2003 >> Aztek FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 9 (Body Control Modules) >> System Tests >> Test C: Scan Tool Does Not Communicate With Electronic Brake Control Module
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test C: Scan Tool Does Not Communicate With Electronic Brake Control Module

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2002 GMC Savana, 2002 Chevrolet Chevy Express, 2001 GMC Savana Special, 2001 GMC Savana Camper Special, and 2001 GMC Savana. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check for open or short to ground in Brown wire (ignition 3 voltage circuit) between instrument panel BRAKE fuse (10-amp) and Electronic Brake Control Module (EBCM) harness connector C1 terminal "A". Check for open or short to ground in Red wire (battery positive voltage circuit) between underhood fuse block ABS fuse (60-amp) and EBCM harness connector C3 terminal "A". See Figure . If both circuits are okay, go to next step. If either circuit is not okay, repair as necessary. After repair, go to step  8 .
  2. Check for an open in Black/White or Tan/White wire (ground circuits) between ground and EBCM harness connector C1 terminal "J" and Black wire between ground and EBCM harness connector C3 terminal "B". If all circuits are okay, go to next step. If any circuit(s) are not okay, repair as necessary. After repair, go to step  8 .
  3. Turn ignition switch to RUN position. Check for short to voltage in Tan/White wire between DLC terminal No. 12 and EBCM harness connector C1 terminal "F". Turn ignition switch to OFF position. Check for open or short to ground in Tan/White wire between DLC terminal No. 12 and EBCM harness connector C1 terminal "F". If circuit is okay, go to next step. If circuit is not okay, repair as necessary. After repair, go to step  6 .
  4. Check EBCM connectors for intermittent or poor terminal contact. See INTERMITTENTS  . If terminal contact is okay, go to next step. If terminal contact is not okay, repair as necessary. After repair, go to step  7 .
  5. Turn ignition switch to RUN position. Check for short to voltage in Yellow wire between EBCM harness connector C2 terminal "D" and left front Wheel Speed Sensor (WSS) harness connector terminal "B". Check for short to voltage in Tan wire between EBCM harness connector C2 terminal "C" and left front Wheel Speed Sensor (WSS) harness connector terminal "A". If both circuits are okay, go to next step. If circuit(s) are not okay, repair as necessary. After repair, go to step  7 .
  6. Replace EBCM. See appropriate ANTI-LOCK BRAKE SYSTEM article in BRAKES.
  7. Connect scan tool to DLC. Turn ignition switch to RUN position. Select display DTCs function for EBCM. If scan tool displays any DTCs which begin with a "U", go to next step. If scan tool displays any DTCs which do not begin with a "U", perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS  .
  8. Using scan tool, clear DTCs. Continue diagnosing or clearing DTCs until all modules have been diagnosed and all DTCs have been cleared.
scientia non olet · About LEMON Manuals