DTC C1850-12 (44-12): Fail Safe Relay Stuck ON

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

DTC (Real Time AWD)

1. Problem verification

   - 1. Turn the vehicle to the ON mode.

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

   Signal	Threshold		Current Conditions
   	Values	Unit	Values	Unit
   Voltage of Battery	More than 8.3	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. Real time AWD relay check

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

   - 2. 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 3.

   NO 

   Replace the REAL TIME AWD RELAY - REMOVAL & INSTALLATION (AWD) .

3. Shorted wire check (E-DPS COIL- line)

   - 1. Disconnect the following connector.

   Real time AWD control unit 24P connector

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

   Test condition	Vehicle OFF (LOCK) mode
   	Real time AWD relay: disconnected
   	Real time AWD control unit 24P connector: disconnected
   Test circuit	E-DPS COIL-
   Test point 1	Real time AWD relay 4P socket No. 4
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   Repair a short to ground in the E-DPS COIL- wire between the real time AWD relay and the real time AWD control unit.

   NO 

   The E-DPS COIL- wire is OK. Go to step 4.

4. Shorted wire check (E-DPS PWR line to power)

   - 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
   	Real time AWD control unit 24P connector: disconnected
   Test circuit	E-DPS PWR
   Test point 1	Real time AWD relay 4P socket No. 2
   Test point 2	Body ground

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

   Is there about 0.1 V or less?

   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 a short to power in the E-DPS PWR wire between the real time AWD relay and the real time AWD control unit.