Dtc P0762 - Workhorse ALLISON 1000MH Service Manual

WORKHORSE CUSTOM CHASSIS
Service Manual

DTC P0762

Circuit Description
The pressure switch manifold (PSM) is a multiple-switch
assembly made up of 3 normally open (N/O) and 1
normally closed (N/C) pressure switches. The pressure
switch 3 (PS3) monitors shift solenoid valve 3 (SS3)
positioning and relays it to the transmission control
module (TCM). When PS3 is in the open state, SS3
should be in the destroked position.
DTC P0762 is a type A DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
• DTC P0762 Shift Solenoid (SS) 3 Valve Performance -
Stuck On
Conditions for Running the DTC
• 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.
• SS3 is commanded to the OFF, destroked, position.
Conditions for Setting the DTC
DTC P0762 sets when SS3 is commanded OFF and PS3 status
remains ON for 2-16 seconds, depending on fl uid temperature.
Action Taken When the DTC Sets
• The TCM illuminates the malfunction indicator lamp
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SECTION
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• When in a forward range and shifting is completed, the
• When in a forward range and the shift is in process, the
• When in NEUTRAL or REVERSE, the transmission will
• While diagnostic response is active, the shift selector
• DTC P0762 is stored in TCM history.
• The TCM freezes shift adapts.
• The TCM inhibits torque converter clutch (TCC)
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
© 2006 Workhorse Custom Chassis — All Rights Reserved
Automatic Transmission – Allison
(MIL).
transmission will fail to another forward range, unless
the transmission is compromised by overspeeding or
direction change, then the transmission will shift to
NEUTRAL.
transmission will return to a previous range, except for
1-2 shifts and 2-1 shifts which will be completed.
fail to NEUTRAL.
is moved from a forward range to NEUTRAL or from a
forward range to REVERSE, the transmission will shift to
NEUTRAL.
engagement.
TCM. Inspect for the following conditions:
– A bent terminal
– A backed-out terminal
– A damaged terminal
2007 W Series Chassis
2007 W Series