PD Mode is used to diagnose Inactive fault codes that may have set during normal operation. This diagnostic mode increases the fault sensing capability of the transmission system, making it more likely to detect intermittent electrical or wiring issues. The PD Mode procedure tests loose, degraded and intermittent connections.

When troubleshooting an Inactive fault code, use the Fault Isolation Procedures to guide you to the wiring and connectors associated with that fault. Once PD Mode is activated, flex the wiring harness and connectors to attempt to recreate the fault.

This procedure may be used prior to performing any troubleshooting or as directed by a Fault Isolation Procedure. PD Mode may be used to troubleshoot intermittent electrical fault issues when there are no Active fault codes present.

PD Mode Inactive Fault Codes

The following is a list of fault codes that work with PD Mode:

13, 14, 15, 16 (86), 17, 19 (89), 22, 29, 33, 34, 35, 36, 43, 44, 46, 51, 52, 56, 57, 58, 61, 63, 65 (95), 66 (96), 67 (97) and 99.

Entering PD Mode

Note: Vehicle must have no Active fault codes.

Note: Vehicle must be stationary, engine off with vehicle parking brake set.

• Turn the ignition on and allow the transmission to fully power up. Verify the transmission is in Neutral.
• Perform two key cycles of the ignition switch starting in the on position and ending in the on position.

  Note: The gear display may flash a “88” at key on, which is a normal power-up test of the display.

  
• The gear display will flash a “25.” Then a solid “PD” to indicate that the transmission has entered PD Mode.

Exiting PD Mode

• Turn the ignition key off. Allow the transmission to completely power down.

Note: The transmission must exit PD Mode before the engine can be started again. The transmission will no longer show “PD” in the gear display when it has exited PD Mode.

Troubleshooting Using PD Mode

• Flex the wiring harness and connector bodies appropriate for the intermittent fault condition while the transmission is in PD Mode.
• “PD” will remain in gear display until an Active fault code has been set during the PD Mode fault isolation procedure.
• If an Active fault code is set during PD Mode, the gear display will display the Active fault code(s). A warning tone will sound when the fault code is Active. The fault code will continue to be shown in the gear display, even if Inactive, until the transmission has powered down.
• Fault codes that occur in PD Mode will not be stored in the TECU as Inactive fault codes.

Identifying a Problem in PD Mode

• Identify any areas of wear or damage to wiring harnesses or connectors.
• If a fault occurs while flexing a connector, exit PD Mode. Disconnect the connector and inspect both sides for damage, corrosion and spread or loose pins.
• Refer to the Fault Code Isolation Procedure Index Fault Code Isolation Procedure Index for the troubleshooting procedures for a specific fault code.