S

DTC Troubleshooting: B1241 or Indicator S

DTC B1241 or DTC indicator S: A Problem in the Blower Motor Circuit

1. Clear the DTC with the HDS.

2. Operate the climate control system in several modes.

3. Check for DTCs using the HDS or the self-diagnostic function.

Is DTC B1241 or S indicated?
YES - Go to step 4.

NO - Intermittent failure. Check for loose wires or poor connections on the blower motor circuit.


4. Turn the ignition switch to LOCK (0).

5. Check the No. 21 (40 A) fuse in the under-hood fuse/relay box, and the No. 30 (10 A) fuse in the under-dash fuse/relay box.

Are the fuses OK?
YES - Go to step 6.

NO - Replace the fuses, and recheck. If the fuses blow again, check for a short in the No. 21 (40 A) and No. 30 (10 A) fuse circuits.


6. Connect the blower motor 2P connector terminal No. 2 to body ground with a jumper wire.

7. Turn the ignition switch to ON (II).

Does the blower motor run?
YES - Go to step 8.

NO - Go to step 23.






8. Turn the ignition switch to LOCK (0).

9. Disconnect the jumper wire.

10. Disconnect the power transistor 5P connector.

11. Check for continuity between the power transistor 5P connector terminal No. 5 and body ground.

Is there continuity?
YES - Go to step 12.

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 G402.





12. Connect the power transistor 5P connector terminals No. 4 and No. 5 with a jumper wire.

13. Turn the ignition switch to ON (II).

Does the blower motor run at high speed?
YES - Go to step 14.

NO - Repair open in the wire between the power transistor and the blower motor.






14. Turn the ignition switch to LOCK (0).

15. Disconnect the jumper wire.

16. Disconnect the climate control unit 30P connector.

17. Check for continuity between body ground and climate control unit 30P connector terminals No. 11 and No. 12 individually.

Is there continuity?
YES - Repair short to body ground in the wire(s) between the climate control unit and the power transistor.

NO - Go to step 18.






18. Check for continuity between the following terminals of the climate control unit 30P connector and the power transistor 5P connector.





Is there continuity?
YES - Go to step 19.

NO - Repair open in the wire(s) between the climate control unit and the power transistor.






19. Turn the ignition switch to ON (II).

20. Measure the voltage between body ground and climate control unit 30P connector terminals No. 11 and No. 12 individually.

Is there voltage?
YES - Repair short to power in the wire(s).

NO - Go to step 21.






21. Reconnect the climate control unit 30P connector.

22. Test the power transistor. Blower Power Transistor Test

Is the power transistor OK?
YES - Check for loose wires or poor connections at the climate control unit 30P connector and the power transistor 5P connector. If the connections are good, substitute a known-good climate control unit, Climate Control Unit Removal/Installation (With Climate Control) and recheck. If the symptom/indication goes away, replace the original climate control unit.

NO - Replace the power transistor.


23. Disconnect the jumper wire.

24. Disconnect the blower motor 2P connector.

25. Measure the voltage between blower motor 2P connector terminal No. 1 and body ground.

Is there battery voltage?
YES - Replace the blower motor.

NO - Go to step 26.






26. Turn the ignition switch to LOCK (0).

27. Remove the blower motor relay from the under-hood fuse/relay box, and test it. Power Relay Test

Is the relay OK?
YES - Go to step 28.

NO - Replace the blower motor relay.


28. Measure the voltage between blower motor relay 4P socket terminal No. 2 and body ground.

Is there battery voltage?
YES - Go to step 29.

NO - Replace the under-hood fuse/relay box. Under-Hood Fuse/Relay Box Removal and Installation






29. Turn the ignition switch to ON (II).

30. Measure the voltage between blower motor relay 4P socket terminal No. 4 and body ground.

Is there battery voltage?
YES - Go to step 31.

NO - Repair open in the wire between the No. 30 (10 A) fuse in the under-dash fuse/relay box and the blower motor relay. If the wire is OK, replace the under-hood fuse/relay box. Under-Hood Fuse/Relay Box Removal and Installation






31. Turn the ignition switch to LOCK (0).

32. Check for continuity between blower motor relay 4P socket terminal No. 3 and body ground.

Is there continuity?
YES - Repair open in the 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 G202