DTC C1850-14 (44-50) (AWD)

DTC C1850-14  : Fail Safe Relay Stuck OFF

NOTE:  Before you troubleshoot, review the General Troubleshooting Information .

DTC (Real Time AWD)

1. Problem verification (with engine idling)

   -1. Turn the vehicle to the ON mode.

   -2. Clear the DTC with the HDS.

   -3. Turn the vehicle to the OFF (LOCK) mode.

   -4. Start the engine.

   -5. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   C1850-14 Fail Safe Relay Stuck OFF

   Is DTC C1850-14 indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

2. Fuse check

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

   -2. Check the following fuse.

   Fuse	No. A20 (20 A)
   Location	Under-hood fuse/relay box

   Is the fuse OK?

   YES 

   The fuse is OK. Reinstall the fuse, then go to step 3.

   NO 

   Replace the fuse. If the fuse blows again, repair a short to ground in the No. A20 (20 A) fuse circuit, then go to step 4

3. Open wire check (+B E-DPS line)

   -1. Disconnect the following connector.

   AWD control unit 24P connector

   -2. Turn the vehicle to the ON mode.

   -3. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode
   	AWD control unit 24P connector: disconnected
   Test point 1	AWD control unit 24P connector No. 2
   Test point 2	Body ground

   Is there battery voltage?

   YES 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good AWD control unit , and recheck. If the symptom/indication goes away with a known-good AWD control unit, replace the original AWD control unit .

   NO 

   Repair an open in the +B E-DPS wire between the No. A20 (20 A) fuse and the AWD control unit.

4. Determine possible failure area (MH line, others)

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

   Test condition	Vehicle OFF (LOCK) mode
   	AWD control unit 24P connector: disconnected
   Test point 1	AWD control unit 24P connector No. 1
   Test point 2	Body ground

   Is there continuity?

   YES 

   Go to step 5.

   NO 

   Go to step 6.

5. Rear differential pump motor internal shorted check

   -1. Disconnect the following connector.

   Rear differential pump motor 2P connector

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

   Test condition	Vehicle OFF (LOCK) mode
   	Real time AWD control unit 24P connector: disconnected
   	Rear differential pump motor 2P connector: disconnected
   Test point 1	Rear differential pump motor 2P connector (male terminals) No. 2:
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   Replace the rear differential pump motor .

   NO 

   Repair a short to ground in the MH wires between the rear differential pump motor and the AWD control unit.

6. Rear differential pump motor internal shorted check

   -1. Disconnect the following connector.

   Rear differential pump motor 2P connector

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

   Test condition	Vehicle OFF mode
   	AWD control unit 24P connector: disconnected
   	Rear differential pump motor 2P connector: disconnected
   Test point 1	Rear differential pump motor 2P connector (male terminals) No. 1:
   Test point 2	Rear differential pump motor 2P connector (male terminals) No. 2:

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

   Is there continuity?

   YES 

   Replace the rear differential pump motor .

   NO 

   Go to step 7.

7. AWD control unit check

   -1. On the AWD control unit side, check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF mode
   	AWD control unit 24P connector: disconnected
   	Rear differential pump motor 2P connector: disconnected
   Test point 1	AWD control unit 24P connector No. 1
   Test point 2	AWD control unit 24P connector No. 3

   Is there continuity?

   YES 

   Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good AWD control unit , and recheck. If the symptom/indication goes away with a known-good AWD control unit, replace the original AWD control unit .

   NO 

   Replace the No. A20 (20 A) fuse.