Allison

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The difference in pressure between main (before the filter) and Torque Converter Clutch (TCC) lockup determines whether to stroke or destroke the Filter Life Indicator (FLI) pressure valve in the prognostics valve body within the control valve module. When this pressure differential exceeds 175-200 kPa (25-30 psi), the FLI pressure valve moves against the return spring and allows control main pressure to open the Pressure Switch 2 (PS2). When the pressure differential is less, the hydraulic circuit to PS2 switch exhausts and closes the PS2 switch.

An active DTC P0847 indicates that the PS2 circuit is detected exhausted (closed) when it should be pressurized (open) while in converter mode.

CONDITIONS FOR RUNNING THE DTC:
1. Prognostics package enabled by calibration.
2. TCM initialized normally and output speed above 25 rpm.
3. TCC solenoid not energized.
4. 40°C (104 °F) ≤ transmission fluid temperature ≤ 150°C (302°F).

CONDITIONS FOR SETTING THE DTC:
1. If PS2 indicates Exhausted in the diagnostic tool while the transmission is in converter mode, then P0847 sets to indicate a PS2 hydraulic or electrical circuit issue.
2. After converter mode cycling, if PS2 state oscillates between pressurized and exhausted more than the switch would be expected in that given period of time based on fluid temperature, and then settles on an unexpected switch state value for the mode of operation, then P0847 sets.

ACTION TAKEN WHEN THE DTC SETS:
When DTC P0847 is active, the following conditions will occur:
1. The CHECK TRANS light illuminates.
2. DTC is stored in TCM history.

CONDITIONS FOR CLEARING THE DTC/CHECK TRANS LIGHT:
Use the diagnostic tool to clear the code. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
Refer to the OEM 4th Generation Control System Operation and Prognostics package and features for important information about Oil Life Monitor (OM), Filter Life Monitor (FM), and Transmission Health Monitor (TM). These sections discuss prognostics principles of operation, feature requirements, maintenance alerts, reports, and processes to reset features or change fluid type (January 2010 and later TCM software) using either the diagnostic tool or an OEM-supplied (MY09 and later) shift selector.

DTC P0847 may be caused by:
1. Pin/terminal damage in a connector populated with wire 118.
2. Shorted wire 118 to chassis or another circuit in vehicle harness.
3. Shorted wire 118 to chassis or another circuit in control module wire harness.
4. Broken or defective connector assemblies allowing pushed back pins to short together.
5. Unlocked connectors, missing seal plugs allowing moisture in connectors.
6. Issue with PS2.
7. Sticky FLI (PS2) pressure valve.
8. Issues with PS2 valve spring.
9. Hydraulic pressure issue e.g., low fluid, low main pressure, low control main pressure, incorrect or damaged control module gasket, etc.
10. Issue with TCM.

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The difference between main pressure (before the filter) and Torque Converter Clutch (TCC) lockup pressure determines whether to stroke or destroke the Filter Life Indicator (FLI) pressure valve in the prognostics valve body within the control valve module. When this pressure differential exceeds 175-200 kPa (25-30 psi), the FLI pressure valve moves against the return spring and allows control main pressure to open the Pressure Switch 2 (PS2). When the pressure differential is less, the hydraulic circuit to PS2 switch exhausts and closes the PS2 switch.

An active DTC P0848 indicates that the PS2 circuit is detected pressurized (open) when it should be exhausted (closed) with ignition ON, engine speed less than 250 rpm and output speed less than 25 rpm.

CONDITIONS FOR RUNNING THE DTC:
1. Prognostics package enabled by calibration.
2. TCM initialized normally and engine speed below 250 rpm and output speed below 25 rpm.
3. TCC solenoid not energized.
4. 40°C (104 °F) ≤ transmission fluid temperature ≤ 150°C (302°F).

CONDITIONS FOR SETTING THE DTC:
If PS2 indicates pressurized in the diagnostic tool at ignition ON and engine below 250 rpm, DTC P0848 sets.

ACTION TAKEN WHEN THE DTC SETS:
When DTC P0848 is active, the following conditions will occur:
1. The CHECK TRANS light illuminates.
2. DTC is stored in TCM history.

CONDITIONS FOR CLEARING THE DTC/CHECK TRANS LIGHT:
Use the diagnostic tool to clear the code. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
Refer to the 4th Generation Control System Operation and Prognostics Package and Features for important information about Oil Life Monitor (OM), Filter Life Monitor (FM), and Transmission Health Monitor (TM). These sections discuss prognostics principles of operation, feature requirements, maintenance alerts, reports, and processes to reset features or change fluid type (January 2010 and later TCM software) using either the diagnostic tool or an OEM-supplied (MY09 and later) shift selector.

DTC P0848 may be caused by:
1. Prognostics enabled calibration and no W118 in chassis harness or non-prognostics control valve module.
2. Open or high resistance in W118 or W158 in chassis harness.
3. Open or high resistance from terminal 17 to PS2 or from PS2 to terminal 19 in control module wire harness.
4. Broken or defective connector assemblies allowing pushed back pins to short together.
5. Unlocked connectors, missing seal plugs allowing moisture in connectors.
6. Issue with PS2.
7. Issue with TCM.

NOTE: This DTC sets only when there is an electrical circuit issue in the PS2 circuit (e.g. (missing W118). Hydraulic circuit troubleshooting is not required.

DIAGNOSTIC RESPONSE:
No

CIRCUIT DESCRIPTION:
The Transmission Control Module (TCM) requires direct battery voltage input to operate. This test detects abnormal power down of battery voltage to the TCM on terminals 10 and 70 with ignition sense ON.

NOTE: The TCM battery power signal must be provided through a 10A or 15A fuse, or a manually-reset circuit breaker.

CONDITIONS FOR RUNNING THE DTC:
1. Engine speed above 350 rpm for at least 0.5 seconds,
2. DTC test runs at after each normal TCM initialization or after TCM reset.

CONDITIONS FOR SETTING THE DTC:
DTC P0880 sets during the next ignition cycle if battery power is lost before the power down process is complete. Normal power down of the TCM takes 2 to 3 seconds after ignition switch input W163 is switched OFF. The selector stays illuminated during this 2 to 3 second process as power OFF data, such as adaptive information, is saved to memory.

ACTION TAKEN WHEN THE DTC SETS:
1. The TCM does not illuminate the CHECK TRANS light.
2. TCM may not reset if ignition is turned OFF.
3. TCM reset.

CONDITIONS FOR CLEARING THE DTC:
Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
1. A defective vehicle battery may allow this DTC to set. Test all vehicle batteries to OEM specifications for proper voltage and load capacity.
2. A defective vehicle charging system may cause this DTC. Test the charging system to all OEM specifications.
3. Battery voltage is available on the diagnostic tool data monitor grid. Prior to ‘Connect’ for the diagnostic tool, check the ‘Troubleshoot Specific Problem’ box under ‘Connection Options’ and then check the ‘Sensor, Voltage, Ohms, and Counts Data’ box.
4. Disconnecting battery power (e.g., via master disconnect) before switching OFF ignition power is a common cause for this DTC. Direct battery power must be maintained for at least 2 to 3 seconds after ignition is switched OFF.
5. Defective TCM may cause this code.

NOTE: If a DTC with either a ‘lock in range’ or ‘shift to alternate range’ response was present during the previous power cycle and a DTC P0880 is detected during TCM initialization, the TCM will not complete initialization. An incomplete TCM initialization is indicated by a specific behavior of the shift selector; (i.e. the shift selector will illuminate all segments in the shift display for 12 or more seconds.) The TCM may still be checked for code history using the diagnostic tool at this time as long as power has been restored to the TCM. Use the troubleshooting manual to troubleshoot stored DTCs that are present during the incomplete TCM initialization.

Review applicable information in Control System and Transmission Specifications to find additional circuit specifications, system and connector diagrams, and troubleshooting tips.

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The Transmission Control Module (TCM) requires direct battery voltage input to operate. This test monitors for low or excessive swings in battery voltage to the TCM on terminals 10 and 70.

NOTE: The TCM battery power signal must be provided through a 10A or 15A fuse, or a manually-reset circuit breaker.

CONDITIONS FOR RUNNING THE DTC:
1. Engine speed above 500 rpm or more for at least 1.5 seconds.
2. DTC test runs at 0.50 second intervals.

CONDITIONS FOR SETTING THE DTC:
DTC P0881 sets when the TCM detects battery voltage is less than 9 volts after engine runtime over 30 seconds.
1. The TCM detects direct battery voltage below 6.5V for longer than 3 seconds with engine speed above 500 rpm.
2. The TCM detects a battery voltage swing of 6V or more for longer than 0.5 seconds with engine speed above 500 rpm.

ACTION TAKEN WHEN THE DTC SETS:
1. The TCM illuminates the CHECK TRANS light.
2. TCM may not reset if ignition is turned OFF.
3. Solenoids OFF (Hydraulic default).
4. TCC solenoid OFF.
5. Main Mod solenoid OFF.

CONDITIONS FOR CLEARING THE DTC:
Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
1. A defective vehicle battery may allow this DTC to set. Test all vehicle batteries to OEM specifications for proper voltage and load capacity.
2. A defective vehicle charging system may cause this DTC. Test the charging system to all OEM specifications. Low voltage or electrically noisy alternators may prevent clean or ample battery voltage from reaching the TCM. If alternator performance is preventing clean battery power on the vehicle, consider using the alternate ignition power diagram shown in OEM Tech Data.
3. Battery voltage is available on the diagnostic tool Data Monitor grid. Prior to ‘Connect’ for the diagnostic tool, check the ‘Troubleshoot Specific Problem’ box under “Connection Options” and then check the ‘Sensor, Voltage, Ohms, and Counts Data’ box.
4. Disconnecting battery power (e.g., via master disconnect) before switching OFF ignition power may cause this DTC. Direct battery power must be maintained for at least 2 to 3 seconds after ignition is switched OFF.
5. Broken or defective connector assemblies allowing pushed back pins to short together.
6. Unlocked connectors, missing seal plugs allowing moisture in connectors.
7. Defective TCM may cause this code.

Review applicable information in Control System and Transmission Specifications to find additional circuit specifications, system and connector diagrams, and troubleshooting tips.

DIAGNOSTIC RESPONSE:
DNS, SOLD OFF (hydraulic default)

CIRCUIT DESCRIPTION:
The Transmission Control Module (TCM) requires direct battery voltage input to operate. This test monitors for low battery voltage to the TCM on terminal 10 and 70.

NOTE: The TCM battery power signal must be provided through a 10A or 15A fuse, or a manually-reset circuit breaker.

CONDITIONS FOR RUNNING THE DTC:
1. Engine speed above 400 rpm for at least 30 seconds.
2. DTC test runs at 0.025 second intervals.

CONDITIONS FOR SETTING THE DTC:
DTC P0882 sets:
When battery voltage is less than 9 volts after engine runtime over 30 seconds.

ACTION TAKEN WHEN THE DTC SETS:
1. The TCM illuminates the CHECK TRANS light.
2. TCM may not re-set if ignition is turned OFF.
3. Solenoids OFF (Hydraulic default).
4. TCC solenoid OFF.
5. Main Mod Solenoid OFF.

CONDITIONS FOR CLEARING THE DTC:
Use the diagnostic service tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
1. A defective vehicle battery may allow this DTC to set. Test all vehicle batteries to OEM specifications for proper voltage and load capacity.
2. A defective vehicle charging system may cause this DTC. Test the charging system to all OEM specifications.
3. Battery voltage is available on the diagnostic tool Data Monitor grid. Prior to ‘Connect’ for the diagnostic tool, check the ‘Troubleshoot Specific Problem’ box under “Connection Options” and then check the ‘Sensor, Voltage, Ohms, and Counts Data’ box.
4. Disconnecting battery power (e.g., via master disconnect) before switching OFF ignition power may cause this DTC. Direct battery power must be maintained for at least 2 to 3 seconds after ignition is switched OFF.
5. Broken or defective connector assemblies allowing pushed back pins to short together.
6. Unlocked connectors, missing seal plugs allowing moisture in connectors.
7. Defective TCM may cause this code.

Review applicable information in Control System and Transmission Specifications to find additional circuit specifications, system and connector diagrams, and troubleshooting tips.

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The Transmission Control Module (TCM) requires direct battery voltage input to operate. This test monitors for high battery voltage to the TCM on terminals 10 and 70.

NOTE: The TCM battery power signal must be provided through a 10a or 15A fuse, or a manually-reset circuit breaker.

CONDITIONS FOR RUNNING THE DTC:
1. Engine speed above 450 rpm for at least 30 seconds.
2. DTC test runs at 0.025 second intervals.

CONDITIONS FOR SETTING THE DTC:
DTC P0883 sets:
1. For a 12V TCM, battery voltage exceeds 18 volts after engine runtime over 1.5 seconds.
2. For a 24V TCM, battery voltage exceeds 32 volts after engine runtime over 1.5 seconds.

ACTION TAKEN WHEN THE DTC SETS:
1. The TCM illuminates the CHECK TRANS light.
2. Solenoids OFF (Hydraulic default).
3. TCC solenoid OFF.
4. Main Mod Solenoid OFF.

CONDITIONS FOR CLEARING THE DTC:
Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
1. A defective vehicle battery may allow this DTC to set. Test all vehicle batteries to OEM specifications for proper voltage and load capacity.
2. A defective vehicle charging system may cause this DTC. Test the charging system to all OEM specifications.
3. Over-voltage from battery charger.
4. Battery voltage is available on the diagnostic tool Data Monitor grid. Prior to ‘Connect’ for the diagnostic tool, check the ‘Troubleshoot Specific Problem’ box under “Connection Options” and then check the ‘Sensor, Voltage, Ohms, and Counts Data’ box.
5. Broken or defective connector assemblies allowing pushed back pins to short together.
6. Unlocked connectors, missing seal plugs allowing moisture in connectors.
7. Defective TCM may cause this code.

Review applicable information in Control System and Transmission Specifications to find additional circuit specifications, system and connector diagrams, and troubleshooting tips.

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The Filter Life Monitor (FM) feature alerts the driver when a filter change is needed by illuminating the SERVICE TRANS indicator (wrench icon display). FM also activates any OEM-provided SERVICE TRANS indicator or datalink message center display (when integrated to receive the message). If the filter is detected as restricted, the wrench icon in the selector flashes ON and OFF for approximately 2 minutes the first time D (Drive) is selected after each engine start. Also, DTC P088A becomes active concurrently with these other visible filter maintenance alerts. This DTC monitors the electrical state of the PS2 FLI pressure switch. If PS2 is detected as open (pressurized) while the transmission is in a forward range and with the Torque Converter Clutch (TCC) (lockup) solenoid energized, the DTC becomes active.

The difference between main pressure (before the filter) and TCC lockup pressure determines whether to stroke or de-stroke the FLI pressure switch valve in the prognostics valve body within the control valve module. An open switch with the TCC solenoid energized causes an active DTC P088A. The CHECK TRANS light does not illuminate for this DTC.

An active DTC and SERVICE TRANS indicator occurs at next engine start when the operator selects D (Drive).

ACTION TAKEN WHEN THE DTC SETS:
1. DTC P088A is stored in the TCM history for a number of ignition cycles.
2. The wrench icon in the shift selector display will flash ON and OFF for approximately 2 minutes the first time D (Drive) is selected after each engine start.

CONDITIONS FOR CLEARING THE DTC:
1. The feature is designed to reset itself automatically after the main filter has been changed.
2. The diagnostic tool can clear the DTC from TCM history.
3. The operator may clear the code and flashing SERVICE TRANS indicator by pressing the MODE button for 10 seconds provided the CMG to disable a reset from the shift selector was not enabled. However, if the filters are not changed, the DTC will most likely become active again.
4. FM may also be reset by selecting N-R-N-R-N-D-N on the shift selector, pausing briefly (less than 3 seconds) between each selector movement when the ignition is on and the engine not running.
5. FM may be reset with a SAE J1939 message.
6. Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
Refer to the OEM 4th Generation Control System Operation and Prognostics Package and Features for important information about OM, FM, and TM. These discuss prognostics principles of operation, feature requirements, maintenance alerts, reports, and processes to reset features or change fluid type (January 2010 and later TCM software) using either the OEM or an OEM-supplied (MY09 and later) shift selector.

The diagnostic tool will show PS2 PRESSURIZED when PS2 is open and PS2 EXHAUSTED when PS2 is closed.

DTC P088A can be caused by:
1. Restricted Main Filter.

NOTE: Change both main and lube filters if main filter is restricted.

2. Low lockup pressure.
3. Open or high resistance in W118 or W158 in chassis harness.
4. Open or high resistance from terminal 17 to PS2, or from PS2 to terminal 19, in control module wire harness.
5. Issue with PS2.
6. Issue with TCM.

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The Filter Life Monitor (FM) feature alerts the driver when a filter change is needed by illuminating the SERVICE TRANS indicator (wrench icon in keypad or lever shift selector display). FM also activates any OEM-provided SERVICE TRANS indicator or datalink message center display (when integrated to receive the message). If the filter is detected as restricted, the wrench icon in the selector flashes ON and OFF for approximately 2 minutes the first time D (Drive) is selected after each engine start. Also, DTC P088A becomes active concurrently with these other visible filter maintenance alerts. This DTC monitors the electrical state of the PS2 Filter Life Indicator (FLI) pressure switch. If PS2 is detected as open (pressurized) while the transmission is in a forward range and with the Torque Converter Clutch (TCC) (lockup) solenoid energized, the DTC becomes active. If several alerts are sent, but the PS2 switch is still detected as pressurized, DTC P088B becomes active.

The difference between main pressure (before the filter) and TCC lockup pressure determines whether to stroke or de-stroke the FLI pressure switch valve in the prognostics valve body within the control valve module.

An active DTC and SERVICE TRANS indicator occurs at next engine start when the operator selects D (Drive).

ACTION TAKEN WHEN THE DTC SETS:
1. DTC P088B is stored in the TCM history for a number of ignition cycles.
2. The wrench icon in the display of a shift selector will flash ON and OFF for approximately 2 minutes the first time D (Drive) is selected after each engine start.
3. The TCM illuminates the CHECK TRANS light.

CONDITIONS FOR CLEARING THE DTC:
1. The feature is designed to reset itself automatically after the main filter has been changed.
2. The diagnostic tool can clear the DTC from TCM history.
3. The operator may clear the code and flashing SERVICE TRANS indicator by pressing the MODE button for 10 seconds provided the CMC to disable a reset from the shift selector was not enabled. However, if the filters are not changed, the DTC will most likely become active again.
4. FM may also be reset by selecting N-R-N-R-N-D-N on the shift selector, pausing briefly (less than 3 seconds) between each selector movement when the ignition is on and the engine not running.
5. FM may be reset with a SAE J1939 message.
6. Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
Refer to the OEM 4th Generation Control System Operation and Prognostics Package and Features for important information about Oil Life Monitor (OM), FM, and Transmission Health Monitor (TM). These sections discuss prognostics principles of operation, feature requirements, maintenance alerts, reports, and processes to reset features or change fluid type (January 2010 and later TCM software) using either the diagnostic tool or an OEM-supplied shift selector.

The diagnostic tool will show PS2 PRESSURIZED when PS2 is open and PS2 EXHAUSTED when PS2 is closed.

DTC P088B can be caused by:
1. Restricted Main Filter.

NOTE: Change both main and lube filters if main filter is restricted.

2. Low lockup pressure.
3. Open or high resistance in W118 or W158 in chassis harness.
4. Open or high resistance from terminal 17 to PS2, or from PS2 to terminal 19, in control module wire harness.
5. Issue with PS2.
6. Issue with TCM.

DIAGNOSTIC RESPONSE:
None

CIRCUIT DESCRIPTION:
The Filter Life Monitor (FM) feature alerts the driver when a filter change is needed by illuminating the SERVICE TRANS indicator (wrench icon in an OEM 4th Generation with Prognostics keypad or lever shift selector display). FM also activates any OEM-provided SERVICE TRANS indicator or datalink message center display (when integrated to receive the message). If the filter is detected as restricted, the wrench icon in the selector flashes ON and OFF for approximately 2 minutes the first time D (Drive) is selected after each engine start. Also, DTC P088A becomes active concurrently with these other visible filter maintenance alerts. This DTC monitors the electrical state of the PS2 Filter Life Indicator (FLI) pressure switch. If PS2 is detected as open (pressurized) while the transmission is in a forward range and with the Torque Converter Clutch (TCC) (lockup) solenoid energized, the DTC becomes active. If several alerts are sent, but the PS2 switch is still detected as pressurized, DTC P088B becomes active.

The difference between main pressure (before the filter) and TCC lockup pressure determines whether to stroke or de-stroke the FLI pressure switch valve in the prognostics valve body within the control valve module. When this pressure differential exceeds 175-200 kPa (25-30 psi), the FLI pressure switch valve moves against the return spring and allows control main pressure to open the PS2 switch. An open switch with the TCC solenoid energized causes an active DTC P088A.

The status of filter restriction is kept in the Transmission Control Module (TCM) power-off data; therefore an active DTC and SERVICE TRANS indicator occurs at next engine start when the operator selects D (Drive).

CONDITIONS FOR RUNNING THE DTC:
1. Enabled by calibration.
2. Filter pressure switch (PS2) is detected on wire 118.
3. Lockup is applied.
4. 40°C (104 °F) ≤ transmission fluid temperature ≤ 150°C (302°F).

CONDITIONS FOR SETTING THE DTC:
PS2 has been detected pressurized (open) while the transmission is in a forward range with the TCC solenoid energized.

ACTION TAKEN WHEN THE DTC SETS:
1. DTC P088B is stored in the TCM history for a number of ignition cycles.
2. The wrench icon in the display of a MY09 and later the OEM 4th Generation shift selector will flash ON and OFF for approximately 2 minutes the first time D (Drive) is selected after each engine start.
3. The TCM illuminates the CHECK TRANS light.

CONDITIONS FOR CLEARING THE DTC:
1. The feature is designed to reset itself automatically after the main filter has been changed.
2. The diagnostic tool can clear the DTC from TCM history.
3. The operator may clear the code and flashing SERVICE TRANS indicator by pressing the MODE button for 10 seconds provided the CMC to disable a reset from the shift selector was not enabled. However, if the filters are not changed, the DTC will most likely become active again.
4. FM may also be reset by selecting N-R-N-R-N-D-N on the shift selector, pausing briefly (less than 3 seconds) between each selector movement when the ignition is on and the engine not running.
5. FM may be reset with a SAE J1939 message.
6. Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.

DIAGNOSTIC AIDS:
Refer to OEM 4th Generation Control System Operation and Prognostics Package and Features for important information about Oil Life Monitor (OM), Filter Life Monitor (FM), and Transmission Health Monitor (TM). These sections discuss prognostics principles of operation, feature requirements, maintenance alerts, reports, and processes to reset features or change fluid type (January 2010 and later TCM software) using either the diagnostic tool or an OEM-supplied (MY09 and later) shift selector.

The diagnostic tool will show PS2 PRESSURIZED when PS2 is open and PS2 EXHAUSTED when PS2 is closed.

DTC P088B can be caused by:
1. Restricted Main Filter.

NOTE: Change both main and lube filters if main filter is restricted.

2. Low lockup pressure.
3. Open or high resistance in W118 or W158 in chassis harness.
4. Open or high resistance from terminal 17 to PS2, or from PS2 to terminal 19, in control module wire harness.
5. Issue with PS2.
6. Issue with TCM.