The input speed sensor helps that ECU to determine when it is time to shift gears up or down. If the signals coming back to the ECU from the sensors does not fall within preset parameters, a P2784 DTC will be stored.
What Transmission Do I Have?
How Serious is the Code?
A P2784 diagnostic trouble code is actually fairly serious, because it means the ECU does not have the data it needs to determine when to actuate a shift.
Symptoms
Symptoms of a P2784 include:
- Harsh shifts
- Erratic shifts
- Failed gear engagement
- Reduced fuel economy
- Non-working or fluctuating speedometer/odometer
- Engine stalling
- Limp Mode
Causes
- Faulty input/turbine speed sensor
- Damaged wiring
- Failed shift solenoid
- Faulty output speed sensor
- Torque convertor issue
- ECU/TCM programming issue
How to Diagnose the Code?
In order to determine the cause of a P2784 OBDII trouble code, the condition and level of transmission fluid first needs to be assessed. Next, the wiring and connectors on the transmission wiring harness need to be checked for signs of damage and corrosion. After that, the input speed sensor will need to be checked. Along with possibly the output speed sensor, engine temperature sensor, shift solenoids and torque converter.
What Transmission Do I Have?
What Repairs Will Fix P2784?
- Change transmission fluid/filter
- Repair/replace wiring or connectors
- Replace input speed sensor
- Replace output speed sensor
- Replace engine temperature sensor
- Replace shift solenoid(s)
- Replace torque converter
Related Codes
N/A
