Test 12B - Bus Bias Level Or Bus (+/-) Open

WARNING: This page is about a different car, the 1995 Plymouth Acclaim and 1995 Dodge Spirit. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION. For wiring diagrams, see article in ENGINE PERFORMANCE:

WIRING DIAGRAMS - 2.5L TBI
WIRING DIAGRAMS - 2.5L FLEXIBLE FUEL
WIRING DIAGRAMS - 3.0L
After each repair, perform TEST VER-1 .

CAUTION: Always turn ignition switch to OFF position prior to disconnecting or connecting any module connector.

NOTE: Ignition off during bus test is most common cause for this trouble code.
1. This test applies to AA body only. If ignition was off during BUS test, turn ignition on. If ignition was on during BUS test, turn ignition on, engine off. Disconnect scan tool. Using an external voltmeter, check voltage between chassis ground and Data Link Connector (DLC) terminal No. 64 (Violet/Brown wire). If voltage is not 2.3-2.6 volts, go to step 3).
2. If voltage is 2.3-2.6 volts, check voltage between chassis ground and DLC terminal No. 4 (White/Black wire). If voltage is not 2.3-2.6 volts, go to next step. If voltage is 2.3-2.6 volts, replace scan tool cable or cartridge as necessary.
3. Turn ignition off, and disconnect Powertrain Control Module (PCM). PCM is located between DLC and battery, on fenderwell. Using an external ohmmeter, check resistance between PCM terminals No. 26 and 46. If resistance is not 100-140 ohms, replace PCM.
4. If resistance is 100-140 ohms, check resistance of Violet/Brown wire between PCM connector terminal No. 26 and DLC terminal No. 6 with scan tool connected to DLC. If resistance is more than 5 ohms, repair open Violet/Brown wire.
5. If resistance is less than 5 ohms, check resistance of White/Black wire between PCM connector terminal No. 46 and DLC terminal No. 4 with scan tool connected to DLC. If resistance is more than 5 ohms, repair open White/Black wire.
6. If resistance is less than 5 ohms and vehicle is not equipped with 41TE transaxle, go to TEST 12G. If resistance is less than 5 ohms and vehicle is equipped with 41TE transaxle, disconnect Transmission Control Module (TCM). TCM is located on left side of engine compartment, near cowl. Check resistance between TCM terminals No. 5 and 44. If resistance is not 100-140 ohms, replace TCM.
7. If resistance is 100-140 ohms, check resistance of Violet/Brown wire between TCM connector terminal No. 43 and DLC terminal No. 6. If resistance is more than 5 ohms, repair open Violet/Brown wire.
8. If resistance is less than 5 ohms, check resistance of White/Black wire between TCM connector terminal No. 4 and DLC terminal No. 4. If resistance is more than 5 ohms, repair open White/Black wire.
9. If resistance is less than 5 ohms, disconnect traveler module. Traveler module is located behind right side of dash, below glove box. Check resistance between traveler module terminals No. 1 and 2. See Figure .
10. If resistance is not 100-140 ohms, replace traveler module. If resistance is 100-140 ohms, check resistance of Violet/Brown wire between traveler module connector terminal No. 1 and DLC terminal No. 6. If resistance is more than 5 ohms, repair open Violet/Brown wire.
11. If resistance is less than 5 ohms, check resistance of White/Black wire between traveler module connector terminal No. 2 and DLC terminal No. 4. If resistance is more than 5 ohms, repair open White/Black wire. If resistance is less than 5 ohms, replace scan tool cable or cartridge as necessary.