WORKHORSE CUSTOM CHASSIS
Service Manual
2007 W Series
SECTION
7.2
PAGE
400
Automatic Transmission – Allison
2007 W Series Chassis
© 2006 Workhorse Custom Chassis — All Rights Reserved
WSM082106
DTC P2670
Step
Action
Value
Yes
No
4
1. Turn the ignition OFF.
2. Disconnect the AT inline 20-way connector.
3. Turn ON the ignition, with the engine OFF. Additional DTCs may set.
4. Using the DMM, measure voltage on the engine side of the AT inline
20-way connector terminal N and ground.
Is the voltage within the specified value?
B+
Go to Step 5
Go to Step 7
5
1. Connect the AT inline 20-way connector.
2. Remove the transmission oil pan. Refer to Oil Pan Replacement .
3. Remove the connectors to the PCS2 and the SS1, SS2 and SS3.
4. Using the DMM, measure the supply voltage of each solenoid con-
nector.
Is the voltage within the specified value at each solenoid terminal?
B+
Go to Step 6
Go to Step 8
6
Test the PCS2 and the SS1, SS2 and SS3 for an open or shorted condi-
tion. Refer to Temperature vs Resistance Solenoid. Refer to Testing for
Continuity and Testing for Short to Ground .
Did you find a condition?
—
Go to Step 9
Go to Step 10
7
Test the HSD2 circuit between the TCM and AT inline 20-way connector for
an open or short to ground. Refer to Testing for Continuity and Testing for
Short to Ground .
Did you find and correct the condition?
—
Go to Step 11
—
8
Replace the AT internal wiring harness. Refer to Wiring Harness
Replacement .
Did you complete the replacement?
—
Go to Step 11
—
9
Replace the open or shorted solenoid. Refer to Control Valve Solenoid
Replacement .
Did you complete the replacement?
—
Go to Step 11
—
