DTC P0816 3.8L
Circuit Description
The TAP Shift system allows the driver to manually shift gears by using the TAP Shift switches located on the steering wheel. Pushing either TAP Shift switch will command an upshift and pulling the switch will command a downshift. The TAP Shift system is activated when the gear selector is in the manual, M, position and is deactivated in all other positions.
If the PCM detects a downshift or an up and downshift request for an extended period of time, then DTC P0816 sets. DTC P0816 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0816 Downshift Switch Circuit
Conditions for Running the DTC
| • | No TAP shift DTC P0815. |
| • | No IMS DTC P1819, P1820, P1822, P1823, P1825, or P1826. |
| • | The time since last gear selector range change is 6 seconds or more. |
Conditions for Setting the DTC
The PCM detects a downshift or an up and downshift request for 1 second in PARK or for 5 minutes in D4 since startup.
Action Taken When the DTC Sets
| • | The PCM does not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM disables TAP Shift operation. |
| • | The PCM assumes D4 for shifting. |
| • | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records. |
| • | The PCM stores DTC P0816 in PCM history. |
Conditions for Clearing the DTC
| • | A scan tool can clear the DTC. |
| • | The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring. |
| • | The PCM cancels the DTC default actions when the fault no longer exists and the DTC passes. |
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||
2 |
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. Does the scan tool Driver Shift Request parameter display None? | -- | Go to Intermittent Conditions in Engine Controls - 3.8L | Go to Step 3 | ||||||
3 | Disconnect the Right TAP Shift Switch connector. Does the Driver Shift Request Status change to None? | -- | Go to Step 6 | Go to Step 4 | ||||||
4 |
Did you find a condition? | 8.11-8.39K ohms Static 2.83-2.93K ohms Upshift 1.25-1.29K ohms Downshift | Go to Step 7 | Go to Step 5 | ||||||
5 |
Caution: Refer to SIR Caution in the Preface section. Test the downshift request circuit for a short to voltage condition between the left and right TAP Shift Switches. Refer to Testing for a Short to Voltage and Wiring Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 9 | Go to Step 8 | ||||||
6 | Replace the Right TAP Shift Switch. Refer to Automatic Transmission Manual Shift Auxiliary Position Switch Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
7 | Replace the Left TAP Shift Switch. Refer to Automatic Transmission Manual Shift Auxiliary Position Switch Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
8 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, set-up and programming. Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
9 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 10 | Go to Step 2 | ||||||
10 | With a 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 in Vehicle DTC Information | System OK |
DTC P0816 5.3L
Circuit Description
The TAP Shift system allows the driver to manually shift gears by using the TAP Shift switches located on the steering wheel. Pushing either TAP Shift switch will command an upshift and pulling the switch will command a downshift. The TAP Shift system is activated when the gear selector is in the manual, M, position and is deactivated in all other positions.
If the TCM detects a downshift or an up and downshift request for an extended period of time, then DTC P0816 sets. DTC P0816 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0816 Downshift Switch Circuit
Conditions for Running the DTC
| • | No TAP shift DTC P0826. |
| • | The engine speed is greater than 500 RPM for 5 seconds. |
| • | The time since last gear selector range change is 6 seconds or more. |
Conditions for Setting the DTC
The TCM detects a downshift or an up and downshift request for 1 second in PARK and for 10 minutes in D4.
Action Taken When the DTC Sets
| • | The TCM does not illuminate the malfunction indicator lamp (MIL). |
| • | The TCM disables TAP Shift operation. |
| • | The TCM commands an alternate coast shift pattern where downshifts occur at higher vehicle speeds while coasting. |
| • | The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records. |
| • | The TCM stores DTC P0816 in PCM history. |
Conditions for Clearing the DTC
| • | A scan tool 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 fault no longer exists and the DTC passes. |
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||
2 |
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 TCM. Does the scan tool Driver Shift Request parameter display None? | -- | Go to Intermittent Conditions in Engine Controls - 5.3L | Go to Step 3 | ||||||
3 | Disconnect the Right TAP Shift Switch connector. Does the Driver Shift Request Status change to None? | -- | Go to Step 6 | Go to Step 4 | ||||||
4 |
Did you find a condition? | 8.11-8.39K ohms Static 2.83-2.93K ohms Upshift 1.25-1.29K ohms Downshift | Go to Step 7 | Go to Step 5 | ||||||
5 |
Caution: Refer to SIR Caution in the Preface section. Test the downshift request circuit for a short to voltage condition between the left and right TAP Shift Switches. Refer to Testing for a Short to Voltage and Wiring Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 9 | Go to Step 8 | ||||||
6 | Replace the Right TAP Shift Switch. Refer to Automatic Transmission Manual Shift Auxiliary Position Switch Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
7 | Replace the Left TAP Shift Switch. Refer to Automatic Transmission Manual Shift Auxiliary Position Switch Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
8 | Replace the TCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup and programming. Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
9 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 10 | Go to Step 2 | ||||||
10 | With a 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 in Vehicle DTC Information | System OK |
