B1840
DTC Troubleshooting: B1840
DTC B1840:
Steering Column Tilt Pulse Failure
NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.
1. Clear the DTCs with the HDS.
2. Turn the ignition switch to LOCK (0), and then back to ON (II), or press the engine start/stop button to select the OFF mode and then the ON mode.
3. Operate the power tilt in each direction with the power tilt/telescopic steering switch.
4. Check for DTCs with the HDS.
Is DTC B1840 indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the tilt position sensor is OK at this time. Check for loose or poor connections.
5. Clear the DTCs with the HDS. Operate the tilt switch in each direction for at least 1 second, then check for DTCs with the HDS.
Is DTC B1841 also indicated?
YES -
Go to step 17.
NO -
Go to step 6.
6. Clear the DTCs with the HDS.
7. Turn the ignition switch to LOCK (0), and then back to ON (II), or press the engine start/stop button to select the OFF mode and then the ON mode.
8. Operate the tilt switch for at least 2 seconds, and check the tilt motor operation.
Does the tilt motor run smoothly?
YES -
Go to step 9.
NO -
Go to step 24.
9. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
10. Disconnect power tilt/telescopic steering control unit connector A (16P).
11. Disconnect the power tilt motor/position sensor 8P connector.
12. Check for continuity between power tilt/telescopic steering control unit connector A (16P) terminals No. 4, No. 12, and No. 16 and power tilt motor/position sensor 8P connector terminals No. 6, No. 7, and No. 8 respectively.
Is there continuity?
YES -
Go to step 13.
NO -
Repair an open or high resistance in the wire(s).
13. Check for continuity between body ground and power tilt/telescopic steering control unit connector A (16P) terminal No. 4 and No. 12 individually.
Is there continuity?
YES -
Repair a short to ground in the wire(s).
NO -
Go to step 14.
14. Reconnect power tilt/telescopic steering control unit connector A (16P).
15. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
16. Measure the voltage between power tilt motor/position sensor 8P connector terminals No. 6 and No. 8, and between terminals No. 7 and No. 8.
Is there about 5 V?
YES -
Faulty power tilt position sensor; replace the steering column assembly Steering Column Removal/Installation.
NO -
If there is no voltage, replace the power tilt/telescopic steering control unit Testing and Inspection. If there is battery voltage, repair a short to power in the wires.
17. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
18. Disconnect power tilt/telescopic steering control unit connector A (16P).
19. Disconnect the power tilt motor/position sensor 8P connector.
20. Check for continuity between power tilt/telescopic steering control unit connector A (16P) terminals No. 2 and No. 16 and power tilt motor/position sensor 8P connector terminals No. 5 and No. 8 respectively.
Is there continuity?
YES -
Go to step 21.
NO -
Repair an open or high resistance in the wire(s).
21. Reconnect power tilt/telescopic steering control unit connector A (16P).
22. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
23. Measure the voltage between power tilt/telescopic steering control unit connector A (16P) terminals No. 2 and No. 16.
Is there battery voltage when the tilt switch is operated?
YES -
Replace the steering column assembly Steering Column Removal/Installation.
NO -
Replace the power tilt/telescopic steering control unit Testing and Inspection.
24. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
25. Check the No. 7 (20 A) fuse in the auxiliary under-hood fuse/relay box.
Is the fuse OK?
YES -
Go to step 26.
NO -
Replace the fuse. If the fuse blows again, repair a short to ground on the No. 7 (20 A) fuse circuit.
26. Measure the voltage between body ground and power tilt/telescopic steering control unit connector B (8P) terminal No. 3.
Is there battery voltage?
YES -
Go to step 27.
NO -
Repair an open or high resistance in the wire between the driver's under-dash fuse/relay box and the power tilt/telescopic steering control unit.
27. Measure the voltage between body ground and power tilt/telescopic steering control unit connector B (8P) terminal No. 1 when operating the tilt up-down switch.
Is there 0.2 V or more?
YES -
Repair an open or high resistance in the wire between the power tilt/telescopic steering control unit and body ground (G403).
NO -
Go to step 28.
28. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
29. Disconnect power tilt/telescopic steering control unit connector B (8P).
30. Disconnect the power tilt motor/position sensor 8P connector.
31. Check for continuity between power tilt/telescopic steering control unit connector B (8P) terminals No. 7 and No. 8 and power tilt motor/position sensor 8P connector terminals No. 2 and No. 3 respectively.
Is there continuity?
YES -
Go to step 32.
NO -
Repair an open or high resistance in the wire(s).
32. Check for continuity between body ground and power tilt motor/position sensor 8P connector terminals No. 2 and No. 3 individually.
Is there continuity?
YES -
Repair a short to ground in the wire(s).
NO -
Go to step 33.
33. Do the tilt motor test Testing and Inspection.
Is the motor OK?
YES -
Replace the power tilt/telescopic steering control unit Testing and Inspection.
NO -
Replace the steering column assembly Steering Column Removal/Installation.