B2140
DTC B2140: Headlight Leveling Motor Signal Circuit Error1. Clear the DTCs with the HDS.
2. Turn the ignition switch OFF, and then back ON (II).
3. Turn the headlight switch ON.
4. Check for DTCs with the HDS.
Is DTC B2140 indicated?
YES - Go to step 5.
NO - Intermittent failure, the adaptive front lighting system is OK at this time. Check for loose or poor connections at the headlight leveling motor connector and at the adaptive front lighting control unit connector.
5. Turn the ignition switch OFF.
6. Disconnect the adaptive front lighting control unit 40P connector.
7. Disconnect the left and right headlight leveling motor 3P connectors.
8. Check for continuity between adaptive front lighting control unit 40P connector terminal No. 36 and body ground.
Is there continuity?
YES - Repair a short in the wire.
NO - Go to step 9.
9. Connect headlight leveling motor 3P connector terminal No. 2 to body ground with a jumper wire.
10. Check for continuity between adaptive front lighting control unit 40P connector terminal No. 36 and body ground.
Is there continuity?
YES - Go to step 11.
NO - Repair an open in the wire.
11. Reconnect the adaptive front lighting control unit 40P connector.
12. Reconnect both headlight leveling motor 3P connectors.
13. Turn the ignition switch ON (II).
14. Measure voltage between adaptive front lighting control unit 40P connector terminals No. 36 (+) and No. 30 (-).
Is there about 0.5 - 4.5 V?
YES - Faulty adaptive front lighting control unit, replace it and do the adaptive front lighting control unit learning procedure.
NO - Go to the headlight leveling motor test. Headlight Leveling Motor Test