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Test 1A - Bus Fault Messages

Battery must be fully charged before proceeding. Connect scan tool to Data Link Connector (DLC) to retrieve messages. Ensure ground circuit has continuity at terminal No. 4 on DLC. Ensure 12 volts exists at terminal No. 16 on DLC. See BUS FAULT MESSAGES table and proceed to appropriate test number. If NO RESPONSE message is displayed, see NO RESPONSE DIAGNOSIS table and proceed to appropriate test number.

BUS FAULT MESSAGES

Fault Messages Test No.
BUS SHORT TO BATTERY TEST 13A
BUS SHORT TO 5 VOLTS TEST 14A
BUS SHORT TO GROUND TEST 15A
BUS (+) & BUS (-) SHORTED TOGETHER TEST 16A
NO TERMINATION TEST 17A
BUS BIAS LEVEL TOO LOW TEST 18A
BUS BIAS LEVEL TOO HIGH TEST 18A
BUS (+) OPEN TEST 19A
BUS (-) OPEN TEST 19A
NO BUS BIAS TEST 4A
NOT RECEIVING BUS MESSAGES CORRECTLY TEST 18A
NO RESPONSE DIAGNOSIS

Problem Module Test No.
Air Bag Control Module TEST 2A 
Automatic Temperature Control TEST 3A 
Body Control Module (1) TEST 4A 
Compass/Mini-Trip Module TEST 5A 
Driver Door Module TEST 6A 
Instrument Cluster TEST 7A 
Memory Seat Module TEST 8A 
Passenger Door Module TEST 9A 
Powertrain Control Module TEST 10A 
CCD Radio TEST 11A 
Vehicle Information Center TEST 12A
(1) Battery power to module disconnected.
NOTE: For connector terminal identification, refer to CONNECTOR IDENTIFICATION  . For wiring diagrams, refer to WIRING DIAGRAMS  . After each repair, perform TEST VER-1A  .
CAUTION: Always turn ignition off prior to disconnecting any module connector.