Service Bay - Vehicle State No. 2

WARNING: This page is about a different variant/trim than selected.

Vehicle state No. 2 is functional ONLY when the engine is running and the selector lever is in PARK or NEUTRAL with engine speed greater than 1, 100 rpm. Vehicle state No. 2 is required when using output state control to carry out a line pressure check. Most, but not all, of the solenoids may be controlled during this vehicle state. It is recommended to use vehicle state No. 1 when using output state control to control the solenoids. The following transmission function and components may be controlled using output state control in vehicle state No. 2.

LINEDSD - Output state control function to command line pressure to a desired pressure
SSD_AMP - Controls the current to SSD, VFS
SSC_AMP - Controls the current to SSC, VFS
SSB_AMP - Controls the current to SSB, VFS
SSA_AMP - Controls the current to SSA, VFS

The vehicle requirements must be met when sending an output state control value to control each component such as the solenoids stated above. If the vehicle requirements are not met when sending the output state control value, an error message may appear. When an error message appears, output state control is cancelled and should be restarted.

After sending the output state control value, if the vehicle requirements are no longer met, the error message will not appear but the output state control value will be cancelled by the TCM. Use the scan tool to monitor the PID that corresponds to each output state control function or component to determine if the TCM is using the output state control value or normal control.

Output state control may be cancelled at any time, to return the TCM to normal control for a specific output state control function or component. See instructions for specific scan tool.

Output state control values for SSA_AMP, SSB_AMP, SSC_AMP, SSD_AMP, LPC_AMP and TCC_AMP to control the current on the VFS solenoids are between zero (0) and one (1) amp. The following are examples.

0 - Commands TCM to control current to zero amps
0.25 - Commands TCM to control current to 1/4 amp or 250 milliamps
0.50 - Commands TCM to control current to 1/2 amp or 500 milliamps
0.75 - Commands TCM to control current to 3/4 amp or 750 milliamps
1 - Commands TCM to control current to 1 amp or 1, 000 milliamps

Output state control aids in testing the electronic functions of the TCM, VFS solenoid and associated circuitry. Output state control allows the technician to control the TCM commanded current of the VFS solenoids and the commanded state of the on/off solenoid. This allows the technician to accurately test the electronic circuitry by comparing the commanded current with the actual current or the on/off state with the actual voltage. Shifting the transmission through the various gears tests the mechanical operation of the VFS solenoids. When using output state control to control the VFS current, the technician may measure the circuit current using an inductive pickup or measure the circuit voltage drop to help verify the proper electrical operation of each VFS solenoid.

The output state control values for LINEDSD to command a desired line pressure are between 414 kPa (60 psi) and 1, 931 kPa (280 psi). The following are examples.

60 psi - Commands TCM to control line pressure to 414 kPa (60 psi)
100 psi - Commands TCM to control line pressure to 689 kPa (100 psi)
150 psi - Commands TCM to control line pressure to 965 kPa (150 psi)
200 psi - Commands TCM to control line pressure to 1, 517 kPa (200 psi)

NOTE: Do NOT command line pressure LOWER then 414 kPa (60 psi) or HIGHER then 1, 931 kPa (280 psi) or damage to the transmission can occur.

Output state control allows the technician to control the TCM commanded line pressure. This allows the technician to accurately test the electronic pressure control system by comparing the output state control commanded line pressure to the actual line pressure indicated on the pressure gauge. The pressure gauge should be connected to the line pressure tap on the transmission. The PID corresponding to the commanded line pressure must be monitored to make sure the TCM is using the output state control value for the commanded line pressure. This test will help verify the correct operation of the transmission pump assembly, pump regulator valve and the operation of the LPC solenoid.