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For 1990-2009 cars only
Makes 🢒 Holden 🢒 2005 🢒 Commodore Executive 🢒 DTC 🢒 DTC P0894

DTC P0894 V8

DTC Description

This diagnostic procedure covers DTC P0894--Transmission Component Slipping.

Circuit Description

The powertrain control module (PCM) monitors the difference between engine speed and transmission output speed. In D3 drive range with the torque converter clutch (TCC) engaged, the engine speed should closely match the transmission output speed. In D4 drive range, with the TCC engaged, the TCC slip speed should be -20 to +50 RPM.

When the PCM detects excessive disparity between the engine speed and transmission output speed, an automatic transmission component slipping DTC will set.

Conditions for Running the DTC
    • No VSS, TCC solenoid, 1-2 Shift Solenoid, 2-3 Shift Solenoid, 3-2 Shift Solenoid, TFP manual valve position switch, or MAF sensor DTCs are set.
    • The engine speed is greater then 450 RPM for 5 seconds.
    • The engine is not in fuel cut-off.
    • The engine torque is 68-542 N·m.
    • The engine vacuum is 0-105 kPa.
    • The TP angle is 20-99 percent.
    • The vehicle speed is between 48-131 km/h.
    • The engine speed is between 1,500-3,000 RPM.
    • The speed ratio is 0.69-0.88. Speed ratio is engine speed divided by the transmission output speed.
    • The gear range is D4.
    • The commanded gear is not 1st gear.
    • The TFT is between 20-150°C.
    • The shift solenoid performance diagnostic counters are zero.

Conditions for Setting the DTC

DTC P0894 sets if the following conditions occur for three TCC cycles:

    • The TCC is commanded on for 5 seconds.
    • The TCC is at 40 percent duty cycle for 5 seconds.
    • The TCC slip speed is 130-800 RPM for 7 seconds.

Important: The following actions may occur before the DTC sets:

If the TCC is commanded on for 5 seconds, the TCC is at 40 percent duty cycle for 5 seconds. The TP angle is 20-99 percent and the transmission slip counter has incremented to either 1 or 2 out of 3, to increment the fail counter for the current ignition cycle, and must occur sequentially:

Condition 1

If the TCC slip speed is 130-80 RPM for 7 seconds, then the PCM will command maximum line pressure, and freeze shift adapts from being updated.

Condition 2

If Condition 1 is met and the TCC slip speed is 130-800 RPM for 7 seconds, then the PCM will command the TCC OFF for 1.5 seconds.

Condition 3

If Condition 2 is met and the TCC slip speed is 130-800 RPM for 7 seconds, then the fail counter on the current ignition cycle is incremented.

The above slip conditions and actions may be disregarded if the TCC is commanded OFF at any time as a result of a driving manoeuvre, or sudden acceleration or deceleration.

Conditions for Clearing the DTC

The Automatic Transmission Component Slipping DTC is a Type B DTC. Refer to Diagnostic Starting Point - Automatic Transmission.

Additional Information
    • Verify that the transmission shift pattern complies with the shift pattern chats. Refer to Functional Test. Other internal transmission failures may cause more than one shift to occur.
    • Refer to Transmission General Information for details of the PCM operation.
    • For an intermittent fault condition, refer to Intermittent Conditions.
    • Since a fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic procedure for shorted terminals or poor wiring connection before replacing any component. Refer to Testing for Intermittent Conditions and Poor Connections for information on electrical fault diagnosis.
    • Refer to Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View , Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid in the diagnosis procedures.

Step

Action

Yes

No

1

Was the Main Diagnostic Table performed?

Go to Step 2

Refer to Diagnostic System Check - Automatic Transmission

2

Inspect for correct transmission fluid level. Refer to Transmission Fluid Check.

Was any fault found and rectified?

Go to Step 12

Go to Step 3

3
  1. Using Tech 2, observe the Freeze Frame/Failure Records for this DTC.
  2. Switch OFF the ignition for 30 seconds.
  3. Operate the vehicle within the Conditions for Running the DTC or within the conditions in the Freeze Frame/Failure Records.
  4. Using Tech 2, select Engine/Diagnostic Trouble Code/Read DTC Information.

Does DTC P0894 fail this ignition cycle?

Go to Step 4

Refer to Diagnostic Aids for the Automatic Transmission Component Slipping DTC

4

Inspect the following solenoids and valves for incorrect operation, blockages and sediment, or damaged seals:

    • Torque convertor clutch solenoid and valve
    • Torque convertor clutch pulse width modulation solenoid and valve
    • 1-2 shift solenoid and valve
    • 2-3 shift solenoid and valve
    • 3-2 shift solenoid and valve

Refer to Torque Converter Diagnosis.

Was any fault found and rectified?

Go to Step 12

Go to Step 5

5

Inspect the valve body assembly for the following conditions:

    • Stuck regulator apply valve
    • Scored regulator apply valve body--Refer to Control Valve Body and Spacer Plate Inspection.

Was any fault found and rectified?

Go to Step 12

Go to Step 6

6

Inspect the torque converter assembly for the following conditions:

    • Front stator shaft busing for wear
    • Stator roller clutch not holding
    • External damage/leaks

Refer to Torque Converter Inspection.

Was any fault found and rectified?

Go to Step 12

Go to Step 7

7

Inspect the oil pump assembly for the following conditions:

    • A stuck converter clutch valve
    • The converter clutch valve is assembled backwards
    • A mispositioned converter clutch valve retaining ring
    • A cocked converter clutch outer valve spring
    • A mis-positioned pump to case gasket
    • Restricted orifice cup plugs
    • Damaged orifice cup plugs
    • Over-tightened, or unevenly tightened, pump body to cover bolts

Refer to Oil Pump Inspection.

Was any fault found and rectified?

Go to Step 12

Go to Step 8

8

Inspect the input housing and shaft assembly for the following conditions:

    • Cut turbine shaft O-ring seal
    • Damaged turbine shaft O-ring seal
    • Restricted or damaged turbine shaft retainer and ball assembly

Refer to Input Internal Gear and Output Shaft Inspection.

Was any fault found and rectified?

Go to Step 12

Go to Step 9

9
  1. Inspect the 2-4 band assembly for the following conditions:
    2. • Worn or damaged 2-4 band
    • Mis-positioned or misassembled 2-4 band
    • The band anchor pin is not engaged
    • Refer to 2-4 Band Inspection.
  2. Inspect the 2-4 servo assembly for the following conditions:
    3. • Blocked or restricted apply passages in the 2-4 servo assembly
    • Nicks or burrs on the 2nd apply piston pin
    • Damaged 2nd apply piston pin
    • Incorrect 2nd apply piston pin
    • Nicks or burrs on the pin bore in the case
    • Damaged fourth servo piston
    • Misassembled fourth servo piston
    • Damaged servo bore in the case
    • Missing piston seals
    • Damaged piston seals
    • Porosity in the pistons, cover, or case
    • Damaged piston seal grooves
    • Plugged orifice cup plug
    • Missing orifice cup plug

Was any fault found and rectified?

Go to Step 12

Go to Step 10

10

Inspect the forward clutch assembly for the following conditions:

    • Worn clutch plates
    • Porosity in the forward clutch piston
    • Damaged forward clutch piston
    • Missing forward clutch piston inner and outer seals
    • Damaged forward clutch piston inner and outer seals
    • Missing input housing to forward clutch housing O-ring seal
    • Cut input housing to forward clutch housing O-ring seal
    • Damaged input housing to forward clutch housing O-ring seal
    • Damaged forward clutch housing
    • Damaged forward clutch housing retainer and ball assembly
    • Forward clutch housing retainer and ball assembly is not sealing

Refer to Forward Clutch Sprag Inspection.

Was any fault found and rectified?

Go to Step 12

Go to Step 11

11

Inspect the 3-4 clutch assembly for the following conditions:

    • Worn clutch plates
    • Porosity in the 3-4 clutch piston
    • Damaged 3-4 clutch piston
    • Missing 3-4 clutch inner and outer seals
    • Damaged 3-4 clutch inner and outer seals
    • Damaged 3-4 clutch spring assembly
    • Damaged 3-4 clutch apply ring
    • Damaged piston seal grooves
    • Plugged orifice cup plug
    • Missing orifice cup plug

Refer to 3-4 Clutch Plate Travel Check.

Was any fault found and rectified?

Go to Step 12

Refer to Diagnostic Aids for the Automatic Transmission Component Slipping DTC

12
  1. Change the automatic transmission fluid and filter. Refer to Automatic Transmission Fluid and Filter Replacement.

    2. Important: The Clear TAPS function will clear all adapt cells. This may affect transmission performance. The PCM will update the transmission adapt cell values as the vehicle is driven.

  2. Using Tech 2, perform the Clear TAPS function.

Was the repair completed?

Go to Step 14

--

13
  1. Using Tech 2, clear the DTCs.
  2. Switch OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC or within the conditions in the Freeze Frame/Failure Records.

Does DTC P0894 fail this ignition cycle?

Go to Step 2

Go to Step 14

14

Using Tech 2, select the DTC Display function.

Are there any DTCs displayed?

Go to appropriate DTC Table

System OK

When all diagnosis and repairs are completed, check the powertrain management system for correct operation.

DTC P0894 V6

DTC Description

This diagnostic procedure supports DTC P0894 Transmission Component Slipping.

Circuit Description

The transmission control module (TCM) monitors the difference between engine speed and transmission output speed. In D3 drive range with the TCC engaged, the engine speed should closely match the transmission output speed. In D4 drive range, with the TCC engaged, the TCC slop speed should be --20 to +50 RPM.

When the TCM detects excessive TCC slip when the TCC should be engaged, the DTC P0894 sets. DTC P0894 is a type B DTC. Refer to Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View , Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid in diagnosis.

Conditions for Running the DTC
    • No DTCs P0122, P0123, P0722, P0723, P0741, P0742, P0751, P0752, P0756, P0757, P0973, P0974, P1810, P1815, P1816, P2763 or P2764.
    • The engine speed is greater than 450 RPM for 5 seconds.
    • The engine is not in fuel cut-off.
    • The engine torque is 108-882 N·m.
    • The vehicle speed is 48-177 km/h.
    • The engine speed is 1,200-3,750 RPM.
    • The speed ratio is 0.70-2.25, speed ration is engine speed divided by the transmission output speed.
    • The gear range is D4.
    • The commanded gear is not 1st gear.
    • The TFT is 20-130°C.
    • The shift solenoid performance diagnostic counters are zero.

Conditions for Setting the DTC

DTC P0894 sets if the following conditions occur for three TCC cycles.

    • The TCC is commanded on for 5 seconds.
    • The throttle position is greater than 10 percent.
    • The TCC slip speed is 100-550 RPM for 10 seconds.

Important: The following actions may occur before the DTC sets. If the:

   • TCC is commanded on for 10 seconds.
   • The TCC is at 75 percent duty cycle for 5 seconds.
   • The TP angle is 10-99 percent.
   • The transmission slip counter has incremented to either 1 or 2, out of 3 to increment the fail counter for the current ignition cycle.
Then the following slip conditions and actions may increment the fail counter for the current ignition cycle. These conditions must occur sequentially.

Condition 1

If the TCC slip speed is 100-550 RPM for 10 seconds, then the TCM will command maximum line pressure and freeze shift adapts from being updated.

Condition 2

If Condition 1 is met and the TCC slip speed is 100-550 RPM for 10 seconds, the TCM will command the TCC off for 1.5 seconds.

Condition 3

If condition 2 is met and the TCC slip speed is 100-550 RPM for 10 seconds, then the fail counter on the current ignition cycle is incremented.

The above slip conditions and actions may be disregarded if the TCC is commanded off at any time, because of a drinking manoeuvre, sudden acceleration or deceleration.

Actions Taken When the DTC sets
    • The TCM requests the ECM to illuminate the check powertrain icon during the second consecutive trip in which the conditions for setting the DTC are met.
    • The TCM commands maximum line pressure.
    • The TCM freezes transmission adaptive functions.
    • The TCM inhibits TCC.
    • The TCM inhibits 4th gear if in hot mode.
    • At the time of the first failure, the TCM records the operating conditions when the conditions for setting the DTC are met. The TCM stores this information as a Failure Record.
    • At the time the second failure, the ECM records the operating conditions when the conditions for setting the DTC are met. The ECM stores this information as a Freeze Frame.
    • The TCM stores DTC P0894 in TCM history during the second consecutive trip in which the conditions for setting the DTC are met.

Conditions for Clearing the DTC
    • The ECM turns off the check powertrain icon after the fourth consecutive drive trip in which the TCM does not sent a check powertrain icon illumination request.
    • Tech 2 can clear the DTC.
    • The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.
    • The TCM cancels the DTC default actions when the ignition is off long enough in order to power down the TCM.

Diagnostic Aids
    • Bronze material found in the transmission oil pan may indicate stator shaft bushing wear. If bushing wear is suspected, inspect the stator shaft and the input, turbine, shaft for damage.
    • Perform the Torque Converter Diagnosis Procedure, refer to Torque Converter Inspection.

Test Description

The following numbers refer to the step numbers in the diagnostic table:

3 Checks the torque converter for slippage while in a commanded lock-up-state.

4-12 Checks the mechanical components that cause the DTC and their state.

13 When the TAP cells are cleared the TCM needs to relearn the TAP cells for the transmission. As such, when the vehicle is first driven, the shifts may be harsh. The transmissions shifts should become smoother the more the vehicle is driven until the TCM has relearned all TAP cells.

Step

Action

Yes

No

1

Has the Diagnostic System Check been performed?

Go to Step 2

Refer to Diagnostic System Check - Automatic Transmission

2

Inspect for correct transmission fluid lever, refer to Transmission Fluid Check.

Did you perform the fluid checking procedure?

Go to Step 3

Check the transmission fluid level, refer to Transmission Fluid Check

3
  1. Connect Tech 2 to the DLC.
  2. Turn on the ignition, with the engine off.

    3. Important: Before clearing the DTC, use the Tech 2 Freeze Frame/Failure Record in order to record the transmission parameters at the time the DTC set. Using Tech 2 to clear the DTC(s) erases the Freeze Frame/Failure Record records from the TCM.

  3. On Tech 2 select: Transmission/Automatic Transmission/Diagnostic Trouble Codes/Freeze Frame.
  4. Select the relevant DTC and note the parameters at the time of the DTC setting.
  5. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  6. Follow the instructions on Tech 2 and clear the DTCs.

    7. Important: It may be necessary to allow multiple TCC cycles to occur in order to verify a slipping condition. It may also be necessary to ensure the transmission is warm before performing this step.

  7. On Tech 2 select Automatic Transmission/Data Display/Transmission Data.
  8. Drive the vehicle in 4th gear with the TCC commanded on.

On Tech 2, while TCC Solenoid status is On, is the TCC Slip Speed within 130-800 RPM for 7 seconds?

Go to Step 4

Refer to Diagnostic Aids within this Section.

4
  1. Inspect the torque converter clutch (TCC) solenoid valve for the following conditions:
    2. • Internal malfunction, such as sediment or damage
    • Damaged seals--Refer to Torque Converter Diagnosis.
  2. Inspect the torque converter clutch (TCC PWM) solenoid valve for the following conditions:
    3. • Internal malfunction, such as sediment or damage
    • Damaged seals--Refer to Torque Converter Inspection.

Did you find and correct the condition?

Go to Step 14

Go to Step 5

5
  1. Inspect the 1-2 shift solenoid (SS) valve for the following conditions:
    2. • Internal malfunction, such as sediment or damage
    • Damaged seals--Refer to Shift Solenoid Valve State and Gear Ratio.
  2. Inspect the 2-3 shift solenoid (SS) valve for the following conditions:
    3. • Internal malfunction, such as sediment or damage
    • Damaged seals--Refer to Shift Solenoid Valve State and Gear Ratio.
  3. Inspect the 3-2 shift solenoid valve assembly for the following conditions:
    4. • Internal malfunction, such as sediment or damage
    • Damaged seals--Refer to Shift Solenoid Valve State and Gear Ratio

Did you find and correct the condition?

Go to Step 14

Go to Step 6

6

Inspect the valve body assembly for the following conditions:

    • Stuck regulator apply valve
    • Scored regulator apply valve body--Refer to Control Valve Body and Spacer Plate Inspection.

Did you find an correct the condition?

Go to Step 13

Go to Step 7

7

Inspect the torque converter assembly for the following conditions:

    • Front stator shaft bushing for wear
    • Stator roller clutch not holding
    • External damage/leaks--Refer to Torque Converter Inspection.

Did you find and correct the condition?

Go to Step 13

Go to Step 8

8

Inspect the oil pump assembly for the following conditions:

    • A stuck converter clutch valve
    • The converter clutch valve is assembled backwards
    • An incorrectly positioned pump to case gasket
    • Restricted orifice cup plugs
    • Damaged orifice cup plugs
    • Over-tightened, or unevenly tightened pump body to cover bolts--Refer to Oil Pump Inspection.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

9

Inspect the input housing and shaft assembly for the following conditions:

    • Cut turbine shaft O-ring seal
    • Damaged turbine shaft O-ring seal
    • Restricted turbine shaft retainer and ball assembly
    • Damaged turbine shaft retainer and ball assembly--Refer to Input Internal Gear and Output Shaft Inspection.

Did you find and correct the condition?

Go to Step 13

Go to Step 10

10
  1. Inspect the 2-4 band assembly for the following conditions:
    2. • Worn 2-4 Band
    • Damaged 2-4 band
    • Incorrectly positioned 2-4 band
    • Incorrectly assembled 2-4 band
    • The band anchor pin is not engaged--Refer to 2-4 Band Inspection.
  2. Inspect the 2-4 servo assembly for the following conditions:
    3. • Restricted apply passages in the 2-4 servo assembly
    • Blocked apply passages in the 2-4 servo assembly
    • Nicks or burrs on the 2nd apply piston pin
    • Damaged 2nd apply piston pin
    • Incorrect 2nd apply piston pi
    • Nicks or burrs on the pin bore in the case
    • Damaged servo bore in the case
    • Missing piston seals
    • Cup piston seals
    • Damaged piston seals
    • Porosity in the pistons
    • Porosity in the cover
    • Porosity in the pistons
    • Porosity in the case
    • Damaged piston seal grooves
    • Plugged office cup plug
    • Missing orifice cup plug--Refer to 2-4 Servo Assembly Inspection.

Did you find and correct the condition?

Go to Step 13

Go to Step 11

11

Inspect the forward clutch assembly for the following conditions:

    • Worn clutch plates
    • Porosity in the forward clutch piston
    • Damaged forward clutch piston
    • Missing forward clutch piston inner and outer seals
    • Cut forward clutch piston inner and outer seals
    • Damaged forward clutch piston
    •  Missing input housing to forward clutch housing O-ring seal
    • Cut input housing to forward clutch housing O-ring seal
    • Damaged forward clutch housing
    • Damaged forward clutch housing retainer and ball assembly
    • Forward clutch housing retainer and ball assembly is not sealing--Refer to Forward Clutch Sprag Inspection.

Did you find and correct the condition?

Go to Step 13

Go to Step 12

12

Inspect the 3-4 clutch assembly for the following conditions:

    • Worn clutch plates
    • Porosity in the 3-4 clutch piston
    • Damaged 3-4 clutch piston
    • Missing 3-4 clutch inner and outer seals
    • Cut 3-4 clutch inner and outer seals
    • Damaged 3-4 clutch inner and outer seals
    • Damaged 3-4 clutch apply ring
    • Damaged piston seal grooves
    • Blocked orifice cup plug
    • Missing oridfice cup plug--Refer to 3-4 Clutch Plate Travel Check.

Did you find and correct the condition?

Go to Step 13

Check for an intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections

13
  1. Change the transmission fluid and filter.
  2. Inspect for correct transmission fluid level, refer to Automatic Transmission Fluid and Filter Replacement.
  3. Add new fluid as necessary.

    4. Important: The Clear TAPS function will clear all adapt cell values as the vehicle is driven.

  4. On Tech 2 select: Transmission/Programming/Reset TAP Cells and follow Tech 2 instructions.

Did you complete the above procedure?

Go to Step 14

--

14

Perform the following procedure in order to verify the repair:

  1. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  2. Follow the instructions on Tech 2 and clear any DTCs.
  3. On Tech 2 select: Automatic Transmission/Data Display/Transmission Data.
  4. Operate the vehicle under the following conditions:
    5. • Drive the vehicle in D4, with the TCC on, and a throttle position at 20%.
    • On Tech 2 ensure the TCC Slip Speed is -20 to +50 RPM for at least 7 seconds.
  5. On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Has DTC P0894 set?

Go to Step 2

Go to Step 15

15

On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Does Tech 2 display any DTCs you have not diagnosed?

Refer to Diagnostic Trouble Code (DTC) List/Type

System OK

When all diagnosis and repairs are completed, check the system for correct operation.