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P0716







P0716-INPUT SPEED SENSOR 1 CIRCUIT PERFORMANCE





For a complete wiring diagram Consult Diagrams/Electrical.

Theory of Operation

The transmission system uses two speed sensors, one to measure input rpm and one to measure output rpm. These inputs are essential for proper transmission operation. Therefore, the integrity of this data is verified through the following checks:

1) When in gear, if the gear ratio does not compare to a known gear ratio, the corresponding in-gear trouble code is set (DTCs P0731-36 and P1736).

2) An excessive change in input or output speeds indicating signal intermittent which will result in the DTCs P0716 and/or P0721 being set.

3) If the common speed sensor ground circuit is lost, both sensor inputs will read the signal from the input speed sensor at idle in neutral. Since the input speed sensor reads 60 teeth from the input clutch hub and the output speed sensor reads 30 teeth from the park gear, the result is an apparent speed ratio of 1:2 and may cause the DTC P1794 to set when at a stop.

- When Monitored:
The transmission gear ratio is monitored continuously while the transmission is in gear.

- Set Condition:
If there is an excessive change in input rpm in any gear. This DTC can take up to five minutes of problem identification before illuminating the MIL.





Always perform the 45RFE/545RFE Pre-Diagnostic Troubleshooting procedure before proceeding. Testing and Inspection

Diagnostic Test

1. CHECK IF DTC IS CURRENT
Start the engine in park.
With the scan tool, monitor the Input Speed Sensor rpm.
Is the Input Speed Sensor rpm below 400 rpm?

Yes

- Go to 2

No

- Go to 9

2. CHECK THE INPUT SPEED SENSOR
Turn the ignition off to the lock position.
Remove the Starter Relay.

CAUTION: Removal of the Starter Relay will prevent the vehicle from being started in gear.

WARNING: The Starter Relay must be removed from the PDC. Failure to do so can result in personal injury or death.

NOTE: Failure to remove the Starter Relay can cause a Transmission - No Response condition.

Install the Transmission Simulator, Miller tool #8333.
Ignition on, engine not running.
With the Transmission Simulator, set the selector switch to 3000/1000 and the Input/Output switch to ON.
With the scan tool, monitor the Input and Output Speed Sensor rpm.
Does the Input speed read 3000 rpm and the Output speed read 1000 rpm ± 50 rpm?

Yes

- Replace the Input Speed Sensor.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Go to 3

3. CHECK THE (T52) INPUT SPEED SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE




Turn the ignition off to the lock position.
Disconnect the PCM C4 harness connector and connect Miller tool #8815.

NOTE: Make sure to leave the Speed Sensor, Transmission Solenoid/TRS Assembly, and Line Pressure Sensor harness connectors disconnected.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller tool #8815 to perform diagnosis.

Remove the Transmission Control Relay.
Place a jumper wire between the (A104) Fused B(+) circuit and the (T16) Transmission Control Relay Output circuit in the Transmission Control Relay connector.
Ignition on, engine not running.
Measure the voltage of the (T52) Input Speed Signal circuit.
Is the voltage above 0.5 volts?

Yes

- Repair the (T52) Input Speed Signal circuit for a short to voltage.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Go to 4

4. CHECK THE (T13) SENSOR GROUND CIRCUIT FOR A SHORT TO VOLTAGE




Measure the voltage of the (T13) Sensor Ground circuit.
Is the voltage above 0.5 volts?

Yes

- Repair the (T13) Sensor Ground circuit for a short to voltage.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Go to 5

5. CHECK THE (T52) INPUT SPEED SIGNAL CIRCUIT FOR AN OPEN




Turn the ignition off to the lock position.
Disconnect the jumper wire between the (A104) Fused B(+) circuit and the (T16) Transmission Control Relay Output circuit in the Transmission Control Relay connector.
Measure the resistance of the (T52) Input Speed Signal circuit between the Input Speed Sensor harness connector and the appropriate terminal of Miller tool #8815.
Is the resistance above 5.0 ohms?

Yes

- Repair the (T52) Input Speed Signal circuit for an open.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Go to 6

6. CHECK THE (T13) SENSOR GROUND CIRCUIT FOR AN OPEN




Measure the resistance of the (T13) Sensor Ground circuit between the Input Speed Sensor harness connector and the appropriate terminal of Miller tool #8815.
Is the resistance above 5.0 ohms?

Yes

- Repair the (T13) Sensor Ground circuit for an open.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Go to 7

7. CHECK THE (T52) INPUT SPEED SIGNAL CIRCUIT FOR A SHORT TO GROUND




Measure the resistance between ground and the Input Speed Signal circuit.
Is the resistance below 5.0 ohms?

Yes

- Repair the (T52) Input Speed Signal circuit for a short to ground.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Go to 8

8. CHECK THE (T13) SENSOR GROUND CIRCUIT FOR A SHORT TO GROUND




Measure the resistance between ground and the (T13) Sensor Ground circuit.
Is the resistance below 5.0 ohms?

Yes

- Repair the (T13) Sensor Ground circuit for a short to ground.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the PCM. With the scan tool, perform Quick Learn.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

9. CHECK WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
Wiggle the wires while checking for shorted and open circuits.
With the scan tool, check the Event Data to help identify the conditions in which the DTC was set.
Were there any problems found?

Yes

- Repair as necessary.
- Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST. Transmission Verification Test

No

- Test Complete.

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