WORKHORSE CUSTOM CHASSIS
Service Manual
2007 W Series
SECTION
7.2
PAGE
156
Automatic Transmission – Allison
2007 W Series Chassis
© 2006 Workhorse Custom Chassis — All Rights Reserved
WSM082106
Conditions for Clearing the DTC
A scan tool can clear the code from TCM history. The
TCM automatically clears the DTC from TCM history if
the vehicle completes 40 warm-up cycles without failure.
Diagnostic Aids
• The TFT should rise steadily during warm-up cycles, then
stabilize.
• DTC P0218 may set after DTC P0711 has set. Follow the
diagnostic table for DTC P0711 before proceeding to the
diagnostic for DTC P0218.
• Inspect the wiring for poor electrical connections at the
TCM. Inspect for the following conditions:
– A bent terminal
– A backed-out terminal
– A damaged terminal
– Poor terminal tension
– A chafed wire
– A broken wire inside the insulation
• When diagnosing for an intermittent short or open,
massage the wiring harness while watching the test
equipment for a change.
• You may have to drive the vehicle in order to experience
a condition.
• An open condition at the circuit may allow a ground path
internally through this circuit. If this occurs, the TCM
sees a temperature that appears to be within normal
operation, approximately -22°C (-7.6°F), and initially
a code will not be set. However, the transmission will
still inhibit shift adapts and TCC operation. It may take
several minutes before DTC P0711 is set to indicate a
failure.
Test Description
The numbers below refer to step numbers on the
diagnostic table.
4. This step tests 5-volt reference.
6. This step tests the TFT sensor and internal wiring
harness.
7. This step tests the resistance of the TFT sensor.
