WORKHORSE CUSTOM CHASSIS
Service Manual
2007 W Series
SECTION
7.2
PAGE
322
Automatic Transmission – Allison
2007 W Series Chassis
© 2006 Workhorse Custom Chassis — All Rights Reserved
WSM082106
DTC P0880
Step
Action
Value
Yes
No
9
Perform the following procedure in order to verify the repair:
1. Clear the DTC.
2. Using the scan tool, monitor system voltage.
3. Select Specific DTC.
4. Enter DTC P0880.
Has the test run and passed?
Go to Step 10
Go to Step 2
10
With the scan tool, observe the stored information, capture info, and DTC
Info.
Does the scan tool display any DTCs that you have not diagnosed?
Go to Diagnostic
Trouble Code (DTC)
List - Vehicle
System OK
DTC P0881
Circuit Description
The transmission control module (TCM) requires direct
battery voltage to operate properly.
DTC P0881 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
• DTC P0881 Transmission Control Module (TCM) Power
Input Signal Performance
Conditions for Running the DTC
• Engine speed is greater than 400 RPM for 0.5 second.
Conditions for Setting the DTC
DTC P0881 sets when the TCM detects a battery direct
voltage variation of 4.0 volts or greater for 30 seconds.
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
