• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

The transmission range control module samples the system voltage on the Ignition 1 voltage circuit every 0.25 s. Lower than normal voltage may be inadequate to operate properly.

The ignition voltage signal is valid, with the ignition turned ON.

The ignition voltage signal is valid, with the Ignition turned OFF.

The transmission range control module detects 6 V or less on the ignition voltage circuit, with the ignition turned ON.

The transmission range control module detects greater than 6 V or greater on the ignition voltage circuit, with the ignition turned OFF.

DTCs P17B3 and P17B4 are Type B DTCs.

DTCs P17B3 and P17B4 are Type B DTCs.

Electronic Transmission Range Selector Schematics

Master Electrical Component List

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Electronic Transmission Range Selector Description

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Control Module References for scan tool information

1. Ignition OFF/Vehicle OFF, and all vehicle systems OFF, disconnect the X1 harness connector at the K173 Transmission Range Control Module. It may take up to 2 min for all vehicle systems to power down .
2. Test for less than 10 Ω between ground circuit terminal 8 and ground.
• If 10 Ω or greater
1. Test for less than 2 Ω in the ground circuit end to end.
• If 2 Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, repair the open/high resistance in the ground connection.
• If less than 10 Ω
3. Ignition ON/Vehicle in Service Mode, verify a test lamp illuminates between B+ circuit terminal 16 and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Ignition OFF/Vehicle OFF.
2. Test for less than 2 Ω in the B+ circuit end to end
• If 2 Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, verify the fuse is good and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Ignition OFF/Vehicle OFF.
2. Test for infinite resistance between the B+ circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If the test lamp illuminates
4. Test for less than 1 V between the ignition circuit terminal 2 and ground.
• If 1 V or greater

  Repair the short to voltage on the circuit.

• If less than 1 V
5. Ignition ON/Vehicle in Service Mode.
6. Verify a test lamp illuminates between terminal 2 and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Ignition OFF/Vehicle OFF.
2. Test for less than 2 Ω in the ignition circuit end to end.
• If 2 Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, refer to Power Mode Mismatch.
• If the test lamp does not illuminate and the circuit fuse is open
1. Ignition OFF/Vehicle OFF.
2. Test for infinite resistance between the ignition circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If the test lamp illuminates
7. Replace the K173 Transmission Range Control Module.

• Perform the Diagnostic Repair Verification after completing the repair.
• Refer to Control Module References for control module replacement, programming, and setup.