DTC B1240 (4b)

DTC B1240 or DTC indicator 4b  : A problem in the mode control motor circuit, linkage, door, or motor

DTCs (AC)

1. Problem verification

   -1. Clear the DTCs with the HDS.

   -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -3. Do the Self-Diagnostic Function with the HDS or the climate control unit .

   -4. Check for DTCs.

   DTC Description	DTC
   B1240 A problem in the mode control motor circuit, linkage, door, or motor

   Is DTC B1240 or 4b indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure. Check for loose wires or poor connections on the mode control motor circuit.

2. Open wire check (M-DEF-DR line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connectors.

   Climate control unit connector B (24P)

   Mode control motor 5P connector

   -3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Climate control unit connector B (24P): disconnected
   	Mode control motor 5P connector: disconnected
   Test point 1	Climate control unit connector B (24P) No. 20
   Test point 2	Mode control motor 5P connector (female terminals) No. 1:

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The M-DEF-DR wire is not open. Go to step 3.

   NO 

   Repair an open in the M-DEF-DR wire.

3. Open wire check (MODE-VENT-DR line)

   -1. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Climate control unit connector B (24P): disconnected
   	Mode control motor 5P connector: disconnected
   Test point 1	Climate control unit connector B (24P) No. 19
   Test point 2	Mode control motor 5P connector (female terminals) No. 2:

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The MODE-VENT-DR wire is not open. Go to step 4.

   NO 

   Repair an open in the MODE-VENT-DR wire.

4. Shorted wire check (M-DEF-DR line)

   -1. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Climate control unit connector B (24P): disconnected
   	Mode control motor 5P connector: disconnected
   Test point 1	Climate control unit connector B (24P) No. 20
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short to ground in the M-DEF-DR wire.

   NO 

   The M-DEF-DR wire is OK. Go to step 5.

5. Shorted wire check (MODE-VENT-DR line)

   -1. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Climate control unit connector B (24P): disconnected
   	Mode control motor 5P connector: disconnected
   Test point 1	Climate control unit connector B (24P) No. 19
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short to ground in the MODE-VENT-DR wire.

   NO 

   The MODE-VENT-DR wire is OK. Go to step 6.

6. Mode control motor check

   -1. Test the mode control motor .

   Is the mode control motor OK?

   YES 

   Replace the climate control unit .

   NO 

   Replace the mode control motor , or repair the mode control linkage or door.