( TL19E1PE10410600000CAAT00 )

Electronic Control System (cont'd)
Lock-up Control
Shift solenoid valve E controls the hydraulic pressure to switch the lock-up shift valve ON and OFF. The PCM actuates shift solenoid valve E and A/T clutch pressure control solenoid valve A to start lock-up. A/T clutch pressure control solenoid valve A applies and regulates hydraulic pressure to the lock-up control valve to control the volume of the lock-up.
The lock-up mechanism operates in D (2nd, 3rd, 4th, and 5th gears), and in S (2nd, 3rd, and 4th gears).
Self-diagnosis
The PCM detects the failure of a signal from a sensor, a switch, and a solenoid valve or from another control unit and stores a Temporary DTC or a DTC. Depending on the failure, a DTC is stored in either the first or the second drive cycle. When a DTC is stored, the PCM blinks the D indicator and/or turns on the malfunction indicator lamp (MIL) by a signal sent to the gauge control module via F-CAN.

- One Drive Cycle Detection Method:
  When an abnormality occurs in the signal from a sensor, a switch, and a solenoid valve or from another control unit, the PCM stores a DTC for the failure and blinks the D indicator and/or turns on the MIL immediately.
- Two Drive Cycle Detection Method:
  When an abnormality occurs in the signal from a sensor, a switch, and a solenoid valve or from another control unit in the first drive cycle, the PCM stores a Temporary DTC. The D indicator and the MIL do not report on at this time. If the failure continues in the second drive cycle, the PCM stores a DTC and blinks the D indicator and/or turns on the MIL.

Fail-safe Function
When an abnormality occurs in the signal from a sensor, a switch, and a solenoid valve or from another control unit, the PCM ignores that signal and substitutes a pre-programmed value for them that allow the automatic transmission to continue driving. This causes a DTC to be stored and the D indicator to blink and/or the MIL to come on.