DTC P1876 Non-Hybrid
Circuit Description
The transmission adaptive pressure (TAP) Shift system allows the driver to manually shift gears by using the TAP Shift switches located on the Automatic Transmission Shifter. Pushing the Up switch will command an upshift and pushing the Down switch will command a downshift. The TAP Shift system is activated when the gear selector is in the D3 position and is deactivated in all other positions.
If the transmission control module (TCM) detects TAP enable switch Active and the TR switch indicates D4, DTC P1876 sets. DTC P1876 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P1876 Up and Down Shift Switch Performance - Range Switch Not in D3
Conditions for Running the DTC
| • | No Transmission range switch DTC P0705. |
| • | No TAP system DTCs P0815, P0816 or P0826. |
| • | No PSA DTCs P1810, P1816, or P1818. |
| • | No TAP system performance DTC 1877. |
| • | No communication DTC U0100. |
| • | The engine run time is greater than 5 seconds. |
Conditions for Setting the DTC
The TCM detects the TAP enable switch is Active and the TR switch is not in D3 for 4 seconds five times during the same trip.
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 P1876 in TCM 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. |
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||
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 Testing for Intermittent Conditions and Poor Connections | Go to Step 3 | ||||||
3 | Select Driver Shift Request on the scan tool. Does the Driver Shift Request parameter display None? | -- | Go to Step 4 | Go to Step 5 | ||||||
4 | Does the Driver Shift Request parameter display Invalid? | -- | Go to Step 9 | Go to Step 8 | ||||||
5 |
Refer to Circuit Protection - Fuses. Was the fuse open? | -- | Go to Step 6 | Go to Step 7 | ||||||
6 |
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematicsfor complete circuit distribution. Refer to Testing for Short to Ground and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 12 | Go to Testing for Intermittent Conditions and Poor Connections | ||||||
7 | Test the ignition 1 voltage circuit of the Floor Shift Control for an open between the fuse block and the Floor Shift Control. Refer to Testing for Continuity and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 8 | ||||||
8 | Test the signal circuit of the Floor Shift Control for an open or short to ground between the Floor Shift Control and the TCM. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 | ||||||
9 |
Is the resistance within the specified range? | 8.11-8.39K Ω | Go to Step 11 | Go to Step 10 | ||||||
10 | Replace the Floor Shift Control. Refer to Transmission Control Replacement. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||||
11 | Replace the TCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||||
12 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 13 | Go to Step 2 | ||||||
13 | 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? | -- | System OK |
