WORKHORSE CUSTOM CHASSIS
Service Manual
2007 W Series
SECTION
7.2
PAGE
274
Automatic Transmission – Allison
2007 W Series Chassis
© 2006 Workhorse Custom Chassis — All Rights Reserved
WSM082106
DTC P0842
Step
Action
Yes
No
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 to the TCM.
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 12
6
1. Turn the ignition OFF.
2. Disconnect the AT inline 20-way connector. Additional DTCs may set.
3. Install the J 44152 jumper harness (20 pins) on the engine side of the AT inline
20-way connector.
4. Turn ON the ignition, with the engine OFF.
5. Using the J 35616 GM terminal test kit and a fused jumper wire, connect termi-
nal D of the J 44152 to ground. Refer to Automatic Transmission Inline Harness
Connector End View.
Does the scan tool indicate PS1 status is LOW when grounded and HIGH when open?
Go to Step 7
Go to Step 11
