P0726 - ENGINE SPEED INPUT CIRCUIT RAGE PERFORMANCE

The DTC P0726 OBDII means that the PCM (Powertrain Control Module) has detected a malfunctioning circuit range regarding the Input Speed Sensor (ISS) input signal. This sensor is located throughout the transmission case near the front of the input shaft. Besides, this sensor is sealed to the gearbox by a rubber gasket on the sensor housing.

This code is stored if the PCM does not receive the expected engine speed input signal voltage in determined time and circumstance. Unacceptable input signals may include insufficient or excessive voltage compared to transmission output speed, engine RPM, or throttle position.  

• Check Engine light ON.
• The transmission shifts may not be performed or may be erratic.
• The transmission goes into limp mode.
• The speedometer may not function properly.
• Inoperative tachometer readings or the tachometer may not work.
• Other input speed codes are stored.

Reasons for setting the P0726 OBD2 fault code:

• The magnetic tip of the ISS sensor may have excess metal debris.
• The Motor Output Speed Sensor may be faulty.
• The Motor Speed Sensor reluctor ring may be worn.
• Circuit wires or connectors may be open or shorted.

Steps for troubleshooting faults caused by the P0726 OBDII diagnostic code:

• Check the condition and level of the transmission fluid. Check for leaks through the lines. If you find some leaks, find the causes and then repair them. Change the fluid if necessary.
• With the required amount of transmission fluid and no leaks, check the cable system and connectors. If you find damage to them, repair or replace them. Then, clear the code.
• Change the Motor Output Speed Sensor.