B1241
DTC Troubleshooting: B1241 (Blower motor lock)
DTC B1241 or Blower motor lock is indicated:
A Problem in the Blower Motor Circuit
1. Clear the DTC with the HDS.
2. Turn the ignition switch to LOCK (0), and then back to ON (II).
3. Do the self-diagnostic with the HDS or the climate control unit.
4. Check for DTCs.
Is DTC B1241 or Blower motor lock indicated?
YES -
Go to step 5.
NO -
Intermittent failure. Check for loose wires or poor connections on the blower motor circuit.
5. Turn the ignition switch to LOCK (0).
6. Check the No. 21 (40 A) fuse in the under-hood fuse/relay box, and the No. 30 (7.5 A) fuse in the driver's under-dash fuse/relay box.
Are the fuses OK?
YES -
Go to step 7.
NO -
Replace the fuse, and recheck. If the fuse blows again, check for a short in the No. 21 (40 A) and No. 30 (7.5 A) fuses circuit.
7. Connect blower motor 2P connector terminal No. 2 to body ground with a jumper wire.
8. Turn the ignition switch to ON (II).
Does the blower motor run?
YES -
Go to step 9.
NO -
Go to step 25.
9. Turn the ignition switch to LOCK (0).
10. Disconnect the jumper wire.
11. Disconnect the power transistor 5P connector.
12. Check for continuity between power transistor 5P connector terminal No. 5 and body ground.
Is there continuity?
YES -
Go to step 13.
NO -
Check for an open in the wire between the power transistor and body ground. If the wire is OK, check for poor ground at G506.
13. Connect power transistor 5P connector terminals No. 4 and No. 5 with a jumper wire.
14. Turn the ignition switch to ON (II).
Does the blower motor run at high speed?
YES -
Go to step 15.
NO -
Repair open in the BLU/RED wire between the power transistor and the blower motor.
15. Turn the ignition switch to LOCK (0).
16. Disconnect the jumper wire.
17. Disconnect the climate control unit 40P connector.
18. Check for continuity between body ground and climate control unit 40P connector terminals No. 9 and No. 10 individually.
Is there continuity?
YES -
Repair a short to body ground in the wire(s) between the climate control unit and the power transistor.
NO -
Go to step 19.
19. Check for continuity between the following terminals of the climate control unit 40P connector and the power transistor 5P connector.
Is there continuity?
YES -
Go to step 20.
NO -
Repair an open in the wire(s) between the climate control unit and the power transistor.
20. Turn the ignition switch to ON (II).
21. Measure the voltage between body ground and climate control unit 40P connector terminals No. 9 and No. 10 individually.
Is there voltage?
YES -
Repair short to power in the wire(s) between the climate control unit and the power transistor. This short may also damage the climate control unit. Repair the short to power before replacing the climate control unit.
NO -
Go to step 22.
22. Turn the ignition switch to LOCK (0).
23. Reconnect the climate control unit 40P connector.
24. Test the power transistor Testing and Inspection.
Is the power transistor OK?
YES -
Check for loose wires or poor connections at the climate control unit 40P connector and at the power transistor 5P connector. If the connections are good, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit Climate Control Unit Removal/Installation.
NO -
Replace the power transistor.
NOTE: If the power transistor is faulty, check the blower motor for damage. If necessary, replace the blower motor before installing a new power transistor.
25. Turn the ignition switch to LOCK (0).
26. Disconnect the jumper wire.
27. Disconnect the blower motor 2P connector.
28. Turn the ignition switch to ON (II).
29. Measure the voltage between blower motor 2P connector terminal No. 1 and body ground.
Is there battery voltage?
YES -
Replace the blower motor Blower Unit Component Replacement.
NO -
Go to step 30.
30. Turn the ignition switch to LOCK (0).
31. Remove the blower motor relay from the under-hood fuse/relay box, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 32.
NO -
Replace the blower motor relay.
32. Measure the voltage between blower motor relay 4P socket terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 33.
NO -
Replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.
33. Turn the ignition switch to ON (II).
34. Measure the voltage between blower motor relay 4P socket terminal No. 4 and body ground.
Is there battery voltage?
YES -
Go to step 35.
NO -
Repair an open in the wire between the No. 30 (7.5 A) fuse in the driver's under-dash fuse/relay box and the blower motor relay.
35. Turn the ignition switch to LOCK (0).
36. Check for continuity between blower motor relay 4P socket terminal No. 3 and body ground.
Is there continuity?
YES -
Repair an open in the WHT wire between the blower motor relay and the blower motor.
NO -
Check for an open in the wire between the blower motor relay and body ground. If the wire is OK, check for poor ground at G301.