DTC C1852-18 (62-01): Solenoid Valve Circuit Low Current

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

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. Start the engine.

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   C1852-18: Solenoid Valve Circuit Low Current

   Is DTC C1852-18 indicated?

   YES 

   The failure is duplicated. Go to step 3.

   NO 

   Go to step 2.

2. Problem verification (with rear differential pump motor running)

   - 1. Clear the DTC with the HDS.

   - 2. Select the ADJUSTMENT in the REAL TIME AWD with the HDS.

   - 3. With the engine running, do the AIR BLEEDING in the ADJUSTMENT with the HDS.

   Air Bleeding

   Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   C1852-18: Solenoid Valve Circuit Low Current

   Is DTC C1852-18 indicated?

   YES 

   The failure is duplicated. Go to step 3.

   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.

3. Determine possible failure area (GND line, others)

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

   Test condition	Vehicle ON mode (idling)
   Test point 1	Rear differential body
   Test point 2	Body ground

   Is there continuity?

   YES 

   Go to step 6.

   NO 

   Go to step 4.

4. Open wire check (GND line)

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

   - 2. Disconnect the following connector.

   Real time AWD control unit 24P connector

   - 3. Check for continuity between the following test points 1 and 2 individually (see table).

   Test condition	Vehicle OFF (LOCK) mode
   	AWD control unit 24P connector: disconnected

   Connector	Test point 1	Test point 2
   Courtesy of HONDA, U.S.A., INC.	No. 4	Body ground
   	No. 8

   Is there continuity?

   YES 

   The GND wires are OK. Go to step 5.

   NO 

   Repair an open in the GND wires between the real time AWD control unit and ground (G603).

5. Open wire check (DG line)

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

   Test condition	Vehicle OFF (LOCK) mode
   	Real time AWD control unit 24P connector: disconnected
   Test point 1	Courtesy of HONDA, U.S.A., INC.
   Test point 2	Rear differential body

   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 

   Check for poor connections or loose terminals between the real time AWD control unit and the rear differential body ground (T7). If the connections are OK, repair an open in the DG wire between the rear differential body and the real time AWD control unit.

6. Determine possible failure area (DUTY1 line, others)

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

   - 2. Disconnect the following connector.

   Rear differential solenoid valve 1P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Wait for 10 seconds.

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

   Test condition	Vehicle ON mode
   	Rear differential solenoid valve 1P connector: disconnected
   Test point 1	Rear differential solenoid valve 1P connector No. 1
   Test point 2	Body ground

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

   Is there about 0.1 V or less?

   YES 

   Go to step 8.

   NO 

   Go to step 7.

7. Shorted wire check (DUTY1 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
   	Rear differential solenoid valve 1P connector: disconnected
   	Real time AWD control unit 24P connector: disconnected
   Test point 1	Rear differential solenoid valve 1P connector No. 1
   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 DUTY1 wire between the rear differential solenoid valve and the real time AWD control unit.

8. Rear differential solenoid valve check

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

   - 2. On the solenoid valve side, measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Rear differential solenoid valve 1P connector: disconnected
   Test point 1	Rear differential solenoid valve 1P connector No. 1
   Test point 2	Rear differential solenoid valve body

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

   Is there about 100 Ω or less?

   YES 

   The rear differential solenoid valve is OK. Go to step 9.

   NO 

   Replace the rear differential solenoid valve - Refer to: REAR DIFFERENTIAL REMOVAL & INSTALLATION(4WD) or REAR DIFFERENTIAL REMOVAL & INSTALLATION(AWD) .

9. Shorted wire check (DUTY1 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
   	Rear differential solenoid valve 1P connector: 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 continuity?

   YES 

   Repair a short to ground in the DUTY1 wire between the rear differential solenoid valve and the real time AWD control unit.

   NO 

   The DUTY1 wire is not shorted. Go to step 10.

10. Open wire check (DUTY1 line)

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

    Test condition	Vehicle OFF (LOCK) mode
    	Rear differential solenoid valve 1P connector: disconnected
    	Real time AWD control unit 24P connector: disconnected
    Test circuit	DUTY1
    Test point 1	Rear differential solenoid valve 1P connector No. 1
    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 DUTY1 wire between the rear differential solenoid valve and the real time AWD control unit.