WORKHORSE CUSTOM CHASSIS
Service Manual
2007 W Series
SECTION
7.2
PAGE
326
Automatic Transmission – Allison
2007 W Series Chassis
© 2006 Workhorse Custom Chassis — All Rights Reserved
WSM082106
DTC P0882
Circuit Description
The transmission control module (TCM) requires direct
battery voltage to operate properly.
DTC P0882 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
• DTC P0882 Transmission Control Module (TCM) Power
Input Signal Low
Conditions for Running the DTC
• Engine speed is greater than 400 RPM for 5 seconds.
Conditions for Setting the DTC
DTC P0882 sets when the TCM detects a battery direct
voltage below 8 volts at 0°C (32°F) for a total of 5 out
of 7 seconds. The voltage threshold is temperature
dependent varying from 5 volts at -60° C (-75°F) to 9
volts at 20° C (68°F).
Action Taken When the DTC Sets
• The TCM does not illuminate the malfunction indicator
lamp (MIL).
• Hydraulic default is commanded. Shift selector position
and hydraulic state of logic valves determine range.
• The TCM inhibits main modulation.
• The TCM inhibits torque converter clutch (TCC)
engagement.
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
• 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.
• A defective vehicle battery may allow this DTC to set.
Test the vehicle battery to verify proper voltage and load
capacity.
• A defective vehicle charging system may cause this DTC
to set.
