Code No.P1787 Damper clutch system (stuck on)


OPERATION



DIAGNOSIS CODE SET CONDITIONS



PROBABLE CAUSES



  • Damaged harness wires and connectors
  • Malfunction of the A/T-ECU
  • Malfunction of damper clutch solenoid valve
  • Malfunction of valve body assembly

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code
If diagnosis code P1787 is stored, the damper clutch solenoid valve may be defective.

Q. Is diagnosis code P1778 (P0740) stored?
Refer to diagnosis code P1778 (P0740): Damper clutch solenoid valve system .
Go to Step 2.

STEP 2. M.U.T.-III data list
Item 10: Damper clutch slip amount (Refer to data list reference table ).

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction .)
Go to Step 3.

STEP 3. Replace the A/T-ECU and then recheck the diagnosis code.
(1)Replace the A/T-ECU.
(2)Test drive the vehicle.
(3)Check the diagnosis code.

Q. Is the diagnosis code stored?
Go to Step 4.
The inspection is complete.

STEP 4. Disassemble, clean and assemble the valve body and recheck the diagnosis code.
(1)Check the mounting bolts for looseness, and the O-ring, solenoid valve and valve body for damage.
Replace the valve body assembly if the damages are thought to be irreparable.
(2)Test drive the vehicle.
(3)Check the diagnosis code.

Q. Is the diagnosis code stored?
Check the torque converter and replace it if necessary.
The inspection is complete.