Dtc P0742 Torque Converter Clutch (Tcc) Circuit Stuck On - Isuzu 1999 RODEO Workshop Manual

7A1–60 TRANSMISSION CONTROL SYSTEM (4L30–E)

DTC P0742 Torque Converter Clutch (TCC) Circuit Stuck On

Circuit Description
The PCM energizes the TCC solenoid by creating a
ignition voltage on circuit RED/YEL.
voltage is energized by the PCM, the TCC solenoid stops
converter signal oil from exhausting.
converter signal oil pressure to increase and move the
TCC valve. The TCC solenoid will deenergize when the
PCM no longer provides an ignition voltage. When the
TCC solenoid is deenergized, it will exhaust fluid and
release the TCC.
This DTC detects low torque converter slip when the TCC
is commanded "off". This is a type "B" DTC.
Conditions For Setting The DTC
The following conditions occur once per TCC cycle, three
consecutive times:
f No TP DTCs P0122 or P0123.
f No OSS DTCs P0722 or P0723.
f No TCC solenoid DTC P1860.
f TP angle is greater than 20%.
f Engine speed is greater than 500 rpm and less than
3000 rpm.
f Engine vacuum is between 0 and 70 kPa.
f Commanded gear is not 1st.
f Gear range is D4.
f TCC is commanded "off".
f No TCC stuck off DTC P1870
f TCC slip speed is between –20 and 40 rpm for 4
seconds.
f Vehicle speed is greater than 25 km/h (15 mph) and
When ignition
less than 120 km/h (75 mph).
f Speed ratio is greater than 0.9 and less than 1.8.
This causes
Action Taken When The DTC Sets
f The PCM will illuminate the Malfunction Indicator
Lamp (MIL) and CHECK TRANS Lamp.
f Inhibit TCC engagement.
Conditions For Clearing The MIL/DTC
f The PCM will turn off the MIL and CHECK TRANS
Lamp after three consecutive ignition cycles without a
failure reported.
f The DTC can be cleared from the PCM history by
using a scan tool.
f The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.
f The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled "off"
long enough to power down the PCM.
D07RW023