DTC Troubleshooting: B1241 (N)
DTC B1241 or DTC indicator N:
 A Problem in the Blower Motor Circuit
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch OFF and then ON (II).
  1. Check for DTCs.
Is DTC B1241 or N indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure, check for loose wires or poor connections on the blower motor circuit.■
  1. Turn the ignition switch OFF.
  1. Check the No. 19 (40 A) fuse in the under-hood fuse/relay box, and the No. 36 (10 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES -
Go to Step 7 .
NO -
Replace the fuses, and recheck. If the fuses blow again, check for a short in the No. 19 (40 A) and No. 36 (10 A) fuses circuit.■
  1. Connect the blower motor 2P connector terminal No. 2 to body ground with a jumper wire.
  1. Turn the ignition switch ON (II).
Does the blower motor run?
YES -
Go to Step 9 .
NO -
Go to Step 24 .
  1. Turn the ignition switch OFF.
  1. Disconnect the jumper wire.
  1. Disconnect the power transistor 4P connector.
  1. Check for continuity between the power transistor 4P connector terminal No. 3 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 G501 for LHD type or G401 for RHD type. ■
  1. Connect the power transistor 4P connector terminals No. 1 and No. 3 with a jumper wire.
  1. Turn the ignition switch ON (II).
Does the blower motor run at high speed?
YES -
Go to Step 15 .
NO -
Repair open in the wire between the power transistor and the blower motor.■
  1. Turn the ignition switch OFF.
  1. Disconnect the jumper wire.
  1. Disconnect the heater control unit 32P connector.
  1. Check for continuity between body ground and the heater control unit 32P connector terminals No. 10 and No. 11 individually.
Is there continuity?
YES -
Repair short to body ground in the wire(s) between the heater control unit and the power transistor.■
NO -
Go to Step 19 .
  1. Check for continuity between the following terminals of the heater control unit 32P connector and the power transistor 4P connector.
    32P:
    4P:
    No. 10
    No. 4
    No. 11
    No. 2

Is there continuity?
YES -
Go to Step 20 .
NO -
Repair open in the wire(s) between the heater control unit and the power transistor.■
  1. Turn the ignition switch ON (II).
  1. Measure the voltage between body ground and the heater control unit 32P connector terminals No. 10 and No. 11 individually.
Is there voltage?
YES -
Repair short to power in the wire(s).■
NO -
Go to Step 22 .
  1. Reconnect the heater control unit 32P connector.
Is the power transistor OK?
YES -
Check for loose wires or poor connections at the heater control unit 32P connector and at the power transistor 4P connector. If the connections are good, substitute a known-good heater control unit, and recheck. If the symptom/indication goes away, replace the original heater control unit .■
NO -
  1. Disconnect the jumper wire.
  1. Disconnect the blower motor 2P connector.
  1. Measure the voltage between the blower motor 2P connector terminal No. 1 and body ground.
Is there battery voltage?
YES -
NO -
Go to Step 27 .
  1. Turn the ignition switch OFF.
  1. Check for an open in the wire between the under-hood fuse/relay box and blower motor 2P connector.
Is the wire OK?
YES -
Check for poor ground at G301. If G301 is OK, replace the under-hood fuse/relay box.■
NO -
Repair open in the wire.■