WORKHORSE CUSTOM CHASSIS
Service Manual
Automatic Transmission – Allison
2007 W Series
© 2006 Workhorse Custom Chassis — All Rights Reserved
SECTION
7.2
PAGE
187
2007 W Series Chassis
WSM082106
DTC P0726
Step
Action
Value
Yes
No
2
1. Install the scan tool.
2. Turn ON the ignition, with the engine OFF.
IMPORTANT:
Before clearing the DTC, use the scan tool in order to
Before clearing the DTC, use the scan tool in order to
record the Freeze Frame and Failure Records for refer-
record the Freeze Frame and Failure Records for refer-
ence. The Clear Info function will erase the data.
ence. The Clear Info function will erase the data.
3. Record the DTC Freeze Frame and Failure Records.
4. Clear the DTC.
5. Using the scan tool, observe ignition voltage.
Is the voltage within the specified range?
9-18 V
Go to Step 3
Go to DTC P0562
for low voltage or
DTC P0563 for
high voltage
3
1. Turn the ignition OFF.
2. Disconnect the 80-way connector at the TCM.
3. Install the J 39700 breakout box, the J-47275 breakout box
adapter and the J 47275-1 magnetic overlay.
4. Using the DMM, measure the resistance between connector ter-
minals 39 and 59.
Is the speed sensor resistance within the specified value?
2,600 ohms @ 25°C
(77°F)
Go to Diagnostic
Aids
Go to Step 4
4
1. Disconnect the wiring harness from the engine speed sensor.
2. Using the DMM and the J 35616 GM terminal test kit, measure
the resistance between the speed sensor terminals.
Is the speed sensor resistance within the specified value?
2,600 ohms @ 25°C
(77°F)
Go to Step 5
Go to Step 6
5
Test the engine speed sensor circuit between the TCM and engine
speed sensor for an open or short to ground condition. Refer to Circuit
Testing .
Did you find and correct the condition?
—
Go to Step 7
—
