Cruze

DTC P0815, P0816, or P0826

When the gear shift lever is placed in manual mode (M), the driver shift request (DSR), also known as the tap shift function, is activated. The DSR allows the vehicle operator to shift gears by pushing the shift lever forward for an upshift or pulling the shift lever rearward for a downshift. The body control module (BCM) supplies battery voltage, ground, and a signal circuit to the shift controller. The shift controller has Hall-effect switches connected to a resistor array. When the lever is in the M position, then pushed forward for an upshift, or pulled rearward for a downshift, a corresponding voltage drop occurs across the resistor network. This voltage drop is monitored by the BCM. The BCM will send the request to the transmission control module to perform the upshift or downshift.

P0815

P0816

P0826

P0815 - Condition 1

The transmission control module (TCM) detects an upshift request for 1 second or greater in PARK, REVERSE, or NEUTRAL.

P0815 - Condition 2

The TCM detects an upshift request for 10 minutes.

P0816 - Condition 1

The TCM detects a downshift request for 1 second in PARK, REVERSE, or NEUTRAL.

P0816 - Condition 2

The TCM detects a downshift request for 10 minutes.

P0826

The TCM detects an invalid voltage on the TAP up/down signal circuit for 1 minute.

P0815, P0816, P0826

P0815, P0816, P0826

DTCs P0815, P0816, and P0826 are Type C DTCs.

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, observe the scan tool Driver Shift Control parameter, while moving the transmission shift through the park, reverse, neutral and drive positions. The reading should display Inactive.
2. Shift lever in the M position, observe the scan tool Driver Shift Request parameter while pushing the shift lever forward and pulling the shift lever rearward. The parameter should change from None to Upshift or Downshift.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Ignition OFF, disconnect the gear shift lever assembly electrical connector from the gear shift lever assembly.
2. Test for less than 10 ohms between the gear shift lever harness connector terminal 2 and ground.

⇒	If greater than the specified range, repair the ground circuit.

3. Ignition ON, verify the scan tool Driver Shift Control parameter displays inactive.

⇒	If not the expected results, test the signal circuit between gear shift lever assembly connector terminal 3 and the BCM for a short-circuit to voltage or ground. If the circuit tests normal, replace the BCM.

4. Ignition OFF, connect a test lamp between gear shift lever harness connector B+ terminal 1 and ground circuit terminal 2.
5. Ignition ON, verify the test lamp is illuminated.

⇒	If the light stays off, test the B+ circuit for an open/high resistance. If the circuit tests normal, replace the BCM.

6. Test for 11-13 volts at the gear shift lever assembly harness connector between signal circuit terminal 3 and ground.

⇒	If not within the specified range, test the signal circuit for a short-circuit to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

7. Ignition OFF, connect the gear shift lever harness connector.
8. Ignition ON, back probe the gear shift lever assembly connector and test for 11-13 volts between terminal 3 and ground with the gear shift lever in park, reverse, neutral, and drive.

⇒	If not within the specified range, replace the gear shift lever assembly.

9. Use a DMM to monitor the voltage between shift lever assembly connector terminal 3 and ground, with the shift selector in the M, tap up, and tap down position. Compare the readings and verify the voltages are correct for each position as follows:

•	Manual: 8.0-10.6 volts

•	Tap down: 5.1-7.3 volts

•	Tap up: 2.0-4.6 volts

⇒	If not within the specified range, test the signal circuit for a short-circuit to ground or open/high resistance. If the circuit tests normal, replace the gear shift lever assembly.

10. If all circuits test normal, replace the BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.