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For 1990-2009 cars only

DTC P1816 2.2L


Object Number: 1453192  Size: MF
Master Electrical Component List
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice
Control Module References

Circuit Description

The automatic transmission fluid pressure (TFP) manual valve position switch consists of three pressure switches. Two of the switches are normally-open, and determine gear range selection. The third switch is normally-closed, and detects torque converter clutch (TCC) release fluid pressure. The TFP manual valve position switch also contains the automatic transmission fluid temperature (TFT) sensor. These components are combined into one unit, attached to the control valve body.

The powertrain control module (PCM) provides battery voltage on the two range signal circuits. By grounding one or more of the switches with fluid pressure from the manual shift valve, the PCM detects the selected gear range. When you disconnect the transmission electrical connector and the ignition is ON, the ground potential for three range signals from the PCM will be removed, and an invalid gear range will be indicated. Refer to Transmission Fluid Pressure Manual Valve Position Switch Logic .

When the PCM detects P/N indicated with a drive gear ratio, DTC P1816 sets. DTC P1816 is a type B DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P1816 Transmission Fluid Pressure (TFP) Valve Position Switch Indicates Park/Neutral (P/N) with Drive Ratio

Conditions for Running the DTC

    • No TP DTCs P0120 or P0220.
    • No VSS DTCs P0502 or P0503.
    • No ISS DTCs P0716 or P0717.
    • No 1-2 SS DTCs P0751, P0752, P0973, or P0974.
    • No 2-3 SS DTCs P0756, P0757, P0976, or P0977.
    • The engine is running for 5 seconds and not in fuel cut off.
    • The OSS is 70 RPM or greater.
    • The TP indicated angle is between 10 and 50 percent.
    • The engine torque is greater than 35 N·m (26 lb ft).

Conditions for Setting the DTC

The PCM detects P/N with a drive ratio less than 0.71 for 5 seconds.

Action Taken When the DTC Sets

    • The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • The PCM commands maximum line pressure.
    • The PCM disables TAP shift operations.
    • The PCM commands an alternate coast shift pattern where downshifts occur at higher speeds while coasting.
    • The PCM freezes transmission adaptive functions.
    • The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
    • The PCM stores DTC P1816 in PCM history during the second consecutive trip in which the Conditions for Setting the DTC are met.

Conditions for Clearing the MIL/DTC

    • The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
    • A scan tool can clear the MIL/DTC.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
    • The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests the integrity of the engine harness and the PCM by checking for the Signal B state change from HI to LOW. A LOW signal indicates the fault is either in the internal transmission harness or the switch. A HI signal indicates the fault is either in the engine harness or the PCM.

DTC P1816

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Important: Before clearing the DTC, use the scan tool in order to record the Failure Records. Using the Clear DTC Information function erases the Failure Records from the PCM.

  4. Record the DTC Failure Records.
  5. Clear the DTC.
  6. Select TFP Sig. B/Sig. C parameter on the scan tool.
  7. Place the range selector in D4.

Does the scan tool TFP Sig. B/Sig. C parameter indicate HI for both?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

  1. Turn OFF the ignition.
  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. Using the J 35616 GM terminal test kit, connect a fused jumper wire from the TFP signal B circuit of the J 44152 to ground. Refer to Automatic Transmission Inline 20-Way Connector End View .
  5. Turn ON the ignition, with the engine OFF.
  6. Select the TFP Sig. B/Sig. C parameter.

Does the TFP Sig. B indicate LOW?

Go to Step 5

Go to Step 4

4

Test the TFP signal B circuit of the TFP manual valve position switch for an open between the PCM and the AT inline 20-way connector.

Refer to Testing for Continuity and Wiring Repairs .

Did you find and correct a condition?

Go to Step 9

Go to Step 8

5

Test the TFP signal B circuit of the TFP manual valve position switch for an open between the AT inline 20-way connector and the TFP manual valve position switch.

Refer to Testing for Continuity .

Did you find and correct a condition?

Go to Step 6

Go to Step 7

6

Replace the automatic transmission wiring harness.

Refer to Wiring Harness Replacement .

Did you complete the replacement?

Go to Step 9

--

7

Replace the TFP manual valve position switch.

Refer to Transmission Fluid Pressure Manual Valve Position Switch Replacement .

Did you complete the replacement?

Go to Step 9

--

8

Replace the PCM.

Refer to Control Module References for replacement, set-up, and programming.

Is the replacement complete?

Go to Step 9

--

9

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear DTC Information.
  3. Start and idle the engine in PARK for 5 seconds.
  4. Select the TFP Sig. B/Sig. C parameter on the scan tool.
  5. Move the range selector from PARK to D4.
  6. Ensure that the TFP signal B changes from HI to LOW.
  7. Select Specific DTC.
  8. Enter DTC P1816.

Has the test run and passed?

Go to Step 10

Go to Step 2

10

With the scan tool, observe the stored information, capture info, and DTC info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK

DTC P1816 3.5L


Object Number: 1453199  Size: MF
Master Electrical Component List
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice
Control Module References

Circuit Description

The automatic transmission fluid pressure (TFP) manual valve position switch consists of three pressure switches. Two of the switches are normally-open, and determine gear range selection. The third switch is normally-closed, and detects torque converter clutch (TCC) release fluid pressure. The TFP manual valve position switch also contains the automatic transmission fluid temperature (TFT) sensor. These components are combined into one unit, attached to the control valve body.

The powertrain control module (PCM) provides battery voltage on the two range signal circuits. By grounding one or more of the switches with fluid pressure from the manual shift valve, the PCM detects the selected gear range. When you disconnect the transmission electrical connector and the ignition is ON, the ground potential for three range signals from the PCM will be removed, and an invalid gear range will be indicated. Refer to Transmission Fluid Pressure Manual Valve Position Switch Logic .

When the PCM detects P/N indicated with a drive gear ratio, DTC P1816 sets. DTC P1816 is a type B DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P1816 Transmission Fluid Pressure (TFP) Valve Position Switch Indicates Park/Neutral (P/N) with Drive Ratio

Conditions for Running the DTC

    • No MAF DTCs P0101, P0102 or P0103.
    • No MAP DTCs P0107 or P0108.
    • No PSA DTCs P1810 or P1818.
    • The engine is running for 5 seconds and not in fuel cut off.
    • The vehicle speed is 5 km/h (3 mph) or more.
    • The TP indicated angle is 10 percent or greater.
    • The engine torque is greater than 34 N·m (25 lb ft).

Conditions for Setting the DTC

The PCM detects P/N with a drive ratio for 5 seconds.

Action Taken When the DTC Sets

    • The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • The PCM disables TAP shift operations.
    • The PCM assumes a D4 shift pattern.
    • The PCM commands an alternate coast shift pattern where downshifts occur at higher speeds while coasting.
    • The PCM freezes transmission adaptive functions.
    • The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
    • The PCM stores DTC P1816 in PCM history during the second consecutive trip in which the Conditions for Setting the DTC are met.

Conditions for Clearing the MIL/DTC

    • The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
    • A scan tool can clear the MIL/DTC.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
    • The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests the integrity of the engine harness and the PCM by checking for the Signal B state change from HI to LOW. A LOW signal indicates the fault is either in the internal transmission harness or the switch. A HI signal indicates the fault is either in the engine harness or the PCM.

DTC P1816

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Important: Before clearing the DTC, use the scan tool in order to record the Failure Records. Using the Clear DTC Information function erases the Failure Records from the PCM.

  4. Record the DTC Failure Records.
  5. Clear the DTC.
  6. Select TFP Sig. B/Sig. C parameter on the scan tool.
  7. Place the range selector in D4.

Does the scan tool TFP Sig. B/Sig. C parameter indicate HI for both?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

  1. Turn OFF the ignition.
  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. Using the J 35616 GM terminal test kit, connect a fused jumper wire from the TFP signal B circuit of the J 44152 to ground. Refer to Automatic Transmission Inline 20-Way Connector End View .
  5. Turn ON the ignition, with the engine OFF.
  6. Select the TFP Sig. B/Sig. C parameter.

Does the TFP Sig. B indicate LOW?

Go to Step 5

Go to Step 4

4

Test the TFP signal B circuit of the TFP manual valve position switch for an open between the PCM and the AT inline 20-way connector.

Refer to Testing for Continuity and Wiring Repairs .

Did you find and correct a condition?

Go to Step 9

Go to Step 8

5

Test the TFP signal B circuit of the TFP manual valve position switch for an open between the AT inline 20-way connector and the TFP manual valve position switch.

Refer to Testing for Continuity .

Did you find and correct a condition?

Go to Step 6

Go to Step 7

6

Replace the automatic transmission wiring harness.

Refer to Wiring Harness Replacement .

Did you complete the replacement?

Go to Step 9

--

7

Replace the TFP manual valve position switch.

Refer to Transmission Fluid Pressure Manual Valve Position Switch Replacement .

Did you complete the replacement?

Go to Step 9

--

8

Replace the PCM.

Refer to Control Module References for replacement, set-up, and programming.

Is the replacement complete?

Go to Step 9

--

9

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear DTC Information.
  3. Start and idle the engine in PARK for 5 seconds.
  4. Select the TFP Sig. B/Sig. C parameter on the scan tool.
  5. Move the range selector from PARK to D4.
  6. Ensure that the TFP signal B changes from HI to LOW.
  7. Select Specific DTC.
  8. Enter DTC P1816.

Has the test run and passed?

Go to Step 10

Go to Step 2

10

With the scan tool, observe the stored information, capture info, and DTC info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK