WORKHORSE CUSTOM CHASSIS
Service Manual
Automatic Transmission – Allison
2007 W Series
© 2006 Workhorse Custom Chassis — All Rights Reserved
SECTION
7.2
PAGE
155
2007 W Series Chassis
WSM082106
DTC P0711
Circuit Description
The transmission fl uid temperature (TFT) sensor is a
part of the pressure switch manifold (PSM) assembly,
and is located in the transmission oil pan. The TFT
sensor is a thermistor, which changes value based
on the temperature of the transmission fl uid. The
transmission control module (TCM) supplies a 5-
volt reference voltage signal to the TFT sensor and
measures the voltage drop in the circuit. When the
transmission is cold, the sensor resistance is high
and the TCM detects high signal voltage. As the fl uid
temperature warms to a normal operating temperature,
the resistance becomes less and the signal voltage
decreases. The TCM uses this information to control
shift quality and torque converter clutch (TCC) apply.
DTC P0711 is a type B DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
• DTC P0711 Transmission Fluid Temperature (TFT)
Sensor Circuit - Performance
Conditions for Running the DTC
• DTC P0712, P0713, P0716, P0717, P0721, and P0722
are not active.
• The components are powered and ignition voltage is
greater than 9.0 volts and less than 18 volts.
• Engine speed is greater than 200 RPM and less than
7,500 RPM for 5 seconds.
• The engine has been running for 2 seconds.
• Engine speed is above 450 RPM and output speed is
above 100 RPM.
• The TFT is in the range of -35°C to +149°C (-31°F to
+300°F).
Conditions for Setting the DTC
DTC P0711 sets when the TCM detects one of the
following conditions:
• The TCM detects a temperature change that is below a
set limit when compared to samples of the minimum and
maximum temperature values.
• The TFT has an unrealistic temperature change of
greater than 10°C (50°F) for 10 occurrences.
• The temperature from startup decreases 40°C (104°F) or
greater within a duration of 6 seconds or greater.
Action Taken When the DTC Sets
• The TCM illuminates the malfunction indicator lamp
(MIL) during the second consecutive trip in which the
Conditions for Setting the DTC are met.
• The TCM freezes shift adapts.
• The TCM records the operating conditions when the
Conditions for Setting the DTC are met. The TCM stores
this information as Failure Records.
• The TCM stores DTC P0711 in TCM history.
• The TCM inhibits TCC engagement.
