P2767-INPUT SPEED SENSOR 2 CIRCUIT NO SIGNAL

For a complete wiring diagram Refer to Section 8W

Theory of Operation

The Input Speed Sensor 2 (N3) is one of two hall effect speed sensors that are used by the Transmission Control Module (TCM) to calculate the transmissions turbine speed. Since the turbine speed could not be measured directly, two of the drive elements are measured. Two input speed sensors are required because both elements are not active in all gears.

• When Monitored:

  Engine speed greater than 450 RPM with none of the following DTCs present: engine speed, TCM undervoltage, output speed sensor, and/or rear wheel speed DTCs. Also required are all wheel speeds above 250 RPM and no wheel slip detected (signal from the ABS system).

• Set Condition:

  If the Input Speed Sensor 2 (N3) signal is equal to 0 RPM.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

Diagnostic Test

NOTE: The Transmission Control Module stores under Environmental Data the transmission operating conditions when the DTC was set. Before erasure of any DTC, record all information pertaining to the DTC, even if there is more than one DTC stored.

• Go To 2

• Go To 10

NOTE: Check connectors - Clean/repair as necessary.

• Repair the (T72) Sensor Supply Voltage circuit for an open.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 3

• Repair the (T71) Input Speed Sensor 2 (N3) Signal circuit for an open.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 4

• Repair the (T13) Sensor Ground circuit for an open.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 5

• Repair the (T71) Input Speed Sensor 2 (N3) Signal circuit for a short to another circuit(s).
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 6

• Repair the (T71) Input Speed Sensor 2 (N3) Signal circuit for a short to ground.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 7

• Repair the (T13) Sensor Ground circuit for a short to another circuit(s)
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 8

• Repair the (T13) Sensor Ground circuit for a short to ground.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Go To 9

WARNING: Properly support the vehicle.

WARNING: To avoid personal injury or death, keep hands and feet clear of rotating wheels.

• Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM per the Service Information. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - REMOVAL)
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Replace the Input Speed Sensor 2 (N3). Refer to 21- AUTOMATIC TRANSMISSION-AUTOMATIC TRANSMISSION NAG1/SERVICE INFORMATION for the appropriate service procedure.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Repair as necessary.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

• Test Complete.