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 an invalid gear range, DTC P1810 sets. DTC P1810 is a type B DTC.
This diagnostic procedure supports the following DTC:
DTC P1810 Transmission Fluid Pressure (TFP) Position Switch Circuit
The engine is running for 5 seconds or more and not in fuel cut off.
The PCM detects an invalid gear range for 60 seconds. Refer to Transmission Fluid Pressure Manual Valve Position Switch Logic .
• | 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 an alternate coast shift pattern where downshifts occur at higher vehicle speeds while coasting. |
• | The PCM assumes a D4 shift pattern. |
• | The PCM freezes transmission adaptive functions. |
• | The PCM disables TAP shift functions, if equipped. |
• | 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 P1810 in PCM history during the second consecutive trip in which the Conditions for Setting the DTC are met. |
• | 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. |
The numbers below refer to the step numbers on the diagnostic table.
This step tests the indicated range signal to the manual valve range actually selected.
This step tests for correct voltage from the PCM.
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 | Did you perform the Transmission Fluid Checking Procedure? | Go to Step 3 | Go to Transmission Fluid Check |
Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM. Does each selected transmission range match the scan tool TFP Sw. display? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 4 | |
4 |
Did the linkage require adjustment? | Go to Step 16 | Go to Step 5 |
5 |
Does the scan tool TFP Sw. Sig. B/Sig. C parameter indicate HI for all range states? | Go to Step 6 | Go to Step 9 |
Refer to Automatic Transmission Inline 20-Way Connector End View . Does the voltage measure ignition voltage at both terminals? | Go to Step 7 | Go to Step 10 | |
7 | Connect a fused jumper wire from the TFP switch signal B circuit of the J 44152 to ground while monitoring the scan tool TFP Sw. Sig. B/Sig. C parameter. Refer to Automatic Transmission Inline 20-Way Connector End View . When the TFP switch signal B circuit is grounded, do any other signal circuits indicate LOW? | Go to Step 11 | Go to Step 8 |
8 | Connect a fused jumper wire from the TFP switch signal C circuit of the J 44152 to ground while monitoring the scan tool TFP Sw. Sig. B/Sig. C parameter. Refer to Automatic Transmission Inline 20-Way Connector End View . When the TFP switch signal C circuit is grounded, do any other signal circuits indicate LOW? | Go to Step 11 | Go to Step 12 |
9 | Test the signal circuits of the TFP manual valve position switch that did not indicate HI for a short to a ground between the PCM connector C3 and the AT inline 20-way connector. Refer to Testing for Short to Ground and Wiring Repairs . Did you find and correct a condition? | Go to Step 16 | Go to Step 15 |
10 | Test the signal circuits of the TFP manual valve position switch that did not indicate ignition voltage for an open between the PCM connector C3 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 16 | Go to Step 15 |
11 | Test the affected signal circuits of the TFP manual valve position switch for a shorted together condition between the PCM connector C3 and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs . Did you find and correct a condition? | Go to Step 16 | Go to Step 15 |
12 | Test the affected signal circuits of the TFP manual valve position switch for an open or shorted condition between the AT inline 20-way connector and the TFP manual valve position switch. Refer to Circuit Testing . Did you find the condition? | Go to Step 13 | Go to Step 14 |
13 | Replace the automatic transmission wiring harness. Refer to Wiring Harness Replacement . Did you complete the replacement? | Go to Step 16 | -- |
14 | 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 16 | -- |
15 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Is the replacement complete? | Go to Step 16 | -- |
16 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | Go to Step 17 | Go to Step 2 |
17 | 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? | System OK |
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 transmission control module (TCM) 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 TCM detects the selected gear range. When you disconnect the transmission electrical connector and the ignition is ON, the ground potential for the range signals from the TCM will be removed, and an invalid gear range will be indicated. Refer to Transmission Fluid Pressure Manual Valve Position Switch Logic .
When the TCM detects an invalid gear range, DTC P1810 sets. DTC P1810 is a type B DTC.
This diagnostic procedure supports the following DTC:
DTC P1810 Transmission Fluid Pressure (TFP) Position Switch Circuit
The engine is running for 5 seconds.
The TCM detects an invalid gear range for 60 seconds. Refer to Transmission Fluid Pressure Manual Valve Position Switch Logic .
• | The TCM illuminates the malfunction indicator lamp (MIL) 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 records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Freeze Frame and Failure Records. |
• | The TCM stores DTC P1810 in TCM history during the second consecutive trip in which the Conditions for Setting the DTC are met. |
• | The TCM 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 TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring. |
• | The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM. |
The numbers below refer to the step numbers on the diagnostic table.
This step tests the indicated range signal to the manual valve range actually selected.
This step tests for correct voltage from the TCM.
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 | Did you perform the Transmission Fluid Checking Procedure? | Go to Step 3 | Go to Transmission Fluid Check |
Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the TCM. Does each selected transmission range match the scan tool TFP Switch display? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 4 | |
4 |
Did the linkage require adjustment? | Go to Step 16 | Go to Step 5 |
5 |
Does the scan tool TFP Sw. Sig. B / Sig. C parameter indicate HI for all range states? | Go to Step 6 | Go to Step 9 |
Refer to Automatic Transmission Inline 20-Way Connector End View . Does the voltage measure ignition voltage at both terminals? | Go to Step 7 | Go to Step 10 | |
7 | Connect a fused jumper wire from the TFP signal B circuit of the J 44152 to ground while monitoring the scan tool TFP Sw. Sig. B / Sig. C parameter. Refer to Automatic Transmission Inline 20-Way Connector End View . When the TFP signal B circuit is grounded, do any other signal circuits indicate LOW? | Go to Step 11 | Go to Step 8 |
8 | Connect a fused jumper wire from the TFP signal C circuit of the J 44152 to ground while monitoring the scan tool TFP Sw. Sig. B / Sig. C parameter. Refer to Automatic Transmission Inline 20-Way Connector End View . When the TFP signal C circuit is grounded, do any other signal circuits indicate LOW? | Go to Step 11 | Go to Step 12 |
9 | Test the signal circuits of the TFP manual valve position switch that did not indicate HI for a short to a ground between the TCM connector and the AT inline 20-way connector. Refer to Testing for Short to Ground and Wiring Repairs . Did you find and correct a condition? | Go to Step 16 | Go to Step 15 |
10 | Test the signal circuits of the TFP manual valve position switch that did not indicate ignition voltage for an open between the TCM connector 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 16 | Go to Step 15 |
11 | Test the affected signal circuits of the TFP manual valve position switch for a shorted together condition between the TCM connector and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs . Did you find and correct a condition? | Go to Step 16 | Go to Step 15 |
12 | Test the affected signal circuits of the TFP manual valve position switch for an open or shorted condition between the AT inline 20-way connector and the TFP manual valve position switch. Refer to Circuit Testing . Did you find the condition? | Go to Step 13 | Go to Step 14 |
13 | Replace the automatic transmission wiring harness. Refer to Wiring Harness Replacement . Did you complete the replacement? | Go to Step 16 | -- |
14 | 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 16 | -- |
15 | Replace the TCM. Refer to Control Module References for replacement, setup, and programming. Is the replacement complete? | Go to Step 16 | -- |
16 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | Go to Step 17 | Go to Step 2 |
17 | 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? | System OK |