Test 1A - Bus Fault Messages
Connect scan tool to Data Link Connector (DLC) to retrieve messages. If scan tool message is blank or no response message is displayed, see NO RESPONSE DIAGNOSIS table and proceed to appropriate test number. Disconnect scan tool. Ensure ground circuit has continuity at DLC terminal No. 4. Ensure 12 volts is present at DLC terminal No. 16. Try another scan tool and/or cable. See BUS FAULT MESSAGES table and proceed to appropriate test number.
NO RESPONSE DIAGNOSIS
| Problem Module | Test No. | ||
|---|---|---|---|
| Air Bag Control Module (ACM) | TEST 2A | ||
| Body Control Module (BCM) (1) | TEST 3A | ||
| Instrument Cluster | TEST 4A | ||
| Compass/Mini-Trip Module | TEST 5A | ||
| Powertrain Control Module (PCM) | TEST 6A | ||
| CCD Radio | TEST 7A | ||
| Transmission Control Module (TCM) | TEST 8A | ||
| Anti-Lock Brake Controller Module | TEST 9A | ||
| HVAC Control Module | TEST 10A | ||
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BUS FAULT MESSAGES
| Fault Messages | Test No. |
|---|---|
| BUS SHORT TO BATTERY | TEST 11A |
| BUS SHORT TO 5 VOLTS | TEST 12A |
| BUS SHORT TO GROUND | TEST 13A |
| BUS (+) & BUS (-) SHORTED TOGETHER | TEST 14A |
| NO TERMINATION | TEST 15A |
| BUS BIAS LEVEL TOO LOW | TEST 16A |
| BUS BIAS LEVEL TOO HIGH | TEST 16A |
| BUS (+) OPEN | TEST 16A |
| BUS (-) OPEN | TEST 16A |
| NO BUS BIAS | TEST 17A |
| NOT RECEIVING BUS MESSAGES CORRECTLY | TEST 18A |