WORKHORSE CUSTOM CHASSIS
Service Manual
Automatic Transmission – Allison
2007 W Series
© 2006 Workhorse Custom Chassis — All Rights Reserved
SECTION
7.2
PAGE
279
2007 W Series Chassis
WSM082106
DTC P0843
Step
Action
Yes
No
2
Measure the transmission fluid level. Refer to Transmission Fluid Checking .
Is the transmission fluid level correct?
Go to Step 3
Go to Transmission
Fluid Checking
3
Measure line pressure. Refer to Line Pressure Check .
Is the pressure within the specified value?
Go to Step 4
Go to Symptoms -
Automatic Transmission
4
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 record the
Before clearing the DTC, use the scan tool in order to record the
Freeze Frame and Failure Records for reference. The Clear Info
Freeze Frame and Failure Records for reference. The Clear Info
function will erase the data.
function will erase the data.
3. Record the DTC Freeze Frame and Failure Records.
4. Clear the DTC.
5. Start the engine.
6. Using the scan tool, monitor PS1 status.
Does the scan tool indicate PS1 status is LOW?
Go to Diagnostic Aids
Go to Step 5
5
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. Turn ON the ignition, with the engine OFF.
5. Connect terminal 17 to ground.
Does the scan tool indicate PS1 status is LOW when grounded and HIGH when open?
Go to Step 6
Go to Step 15
