DTC C1850-14 (44-50): Fail Safe Relay Stuck OFF

NOTE:  Before you troubleshoot, Refer to: HOW TO TROUBLESHOOT THE REAL TIME AWD SYSTEM (AWD) .

DTC (Real Time AWD)

1. Problem verification

   - 1. Start the engine.

   - 2. Check the parameter(s) below with the HDS.

   Signal	Threshold		Current Conditions
   	Values	Unit	Values	Unit
   Voltage of Battery	Less than 3.0	V

   Do the current condition(s) match the threshold?

   YES 

   The failure is duplicated. 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. A1-5 (30 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, and recheck. If the fuse blows again, repair a short to ground in the No. A1-5 (30 A) fuse circuit.

3. Real time AWD relay check

   - 1. Remove the real time AWD relay, then test it.

   Is the real time AWD relay OK?

   YES 

   The real time AWD relay is OK. Go to step 4.

   NO 

   REAL TIME AWD RELAY REMOVAL & INSTALLATION(AWD) .

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

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

   Test condition	Vehicle OFF (LOCK) mode
   	Real time AWD relay: disconnected
   Test point 1	Real time AWD relay 4P socket No. 1
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   The +B E-DPS wire is OK. Go to step 5.

   NO 

   Repair an open in the +B E-DPS wire between the real time AWD relay and the No. A1-5 (30 A) fuse in the under-hood fuse/relay box.

5. Open wire check (IG1 P/W line)

   - 1. Turn the vehicle to the ON mode.

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

   Test condition	Vehicle ON mode
   	Real time AWD relay: disconnected
   Test point 1	Real time AWD relay 4P socket No. 3
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   The IG1 P/W wire is OK. Go to step 6.

   NO 

   Repair an open in the IG1 P/W wire between the real time AWD relay and the No. B6 (7.5 A) fuse in the under-dash fuse/relay box.

6. Shorted wire check (E-DPS COIL- line to power)

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

   - 2. Disconnect the following connector.

   Real time AWD control unit 24P connector

   - 3. Turn the vehicle to the ON mode.

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

   Test condition	Vehicle ON mode
   	Real time AWD relay: disconnected
   	Real time AWD control unit 24P connector: disconnected
   Test point 1	Courtesy of HONDA, U.S.A., INC.
   Test point 2	Body ground

   Is there about 0.1 V or less?

   YES 

   The E-DPS COIL- wire is not shorted to power. Go to step 7.

   NO 

   Repair a short to power in the E-DPS COIL- wire between the real time AWD relay and the real time AWD control unit, then REAL TIME AWD CONTROL UNIT REMOVAL & INSTALLATION(AWD) .

7. Open wire check (E-DPS COIL- line)

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

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

   Test condition	Vehicle OFF mode
   	Real time AWD relay: disconnected
   	Real time AWD control unit 24P connector: disconnected
   Test point 1	Real time AWD relay 4P socket No. 4
   Test point 2	Courtesy of HONDA, U.S.A., INC.

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

   Is there continuity?

   YES 

   The E-DPS COIL- wire is OK. Go to step 8.

   NO 

   Repair an open in the E-DPS COIL- wire between the real time AWD relay and the real time AWD control unit.

8. Open wire check (E-DPS PWR line)

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

   Test condition	Vehicle OFF mode
   	Real time AWD relay: disconnected
   	Real time AWD control unit 24P connector: disconnected
   Test point 1	Real time AWD relay 4P socket No. 2
   Test point 2	Courtesy of HONDA, U.S.A., INC.

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

   Is there continuity?

   YES 

   Update the real time AWD control unit if it does not have the latest software , or substitute a known-good real time AWD control unit , and recheck. If the symptom/indication goes away with the updated real time AWD control unit, troubleshooting is complete. If the symptom/indication goes away with a known-good real time AWD control unit, replace the original real time AWD control unit .

   NO 

   Repair an open in the E-DPS PWR wire between the real time AWD relay and the real time AWD control unit.